Descriptor: "Local density of states" / Publisher: hal ccsd - Searchworks@Jio Institute Digital Library Search Results

Your search keyword '"Local density of states"' showing total 72 results

Start Over Descriptor "Local density of states" Publisher hal ccsd

72 results on '"Local density of states"'

1. Importance of accurately measuring LDOS maps using scanning tunneling spectroscopy in materials presenting atom-dependent charge order: The case of the correlated Pb/Si(111) single atomic layer

Author: C. Tresca, T. Bilgeri, G. Ménard, V. Cherkez, R. Federicci, D. Longo, M. Hervé, F. Debontridder, P. David, D. Roditchev, G. Profeta, T. Cren, M. Calandra, C. Brun, Spectroscopie des nouveaux états quantiques (INSP-E2), Institut des Nanosciences de Paris (INSP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Department of Physical and Chemical Sciences [L'Aquila] (DSFC), Università degli Studi dell'Aquila = University of L'Aquila (UNIVAQ), Physique Mésoscopique, Laboratoire de physique de l'ENS - ENS Paris (LPENS), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Département de Physique de l'ENS-PSL, École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Département de Physique de l'ENS-PSL, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Institut de Mécanique Céleste et de Calcul des Ephémérides (IMCCE), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Lille-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique et d'Etude des Matériaux (UMR 8213) (LPEM), Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), University of Trento [Trento], and ANR-11-IDEX-0004,SUPER,Sorbonne Universités à Paris pour l'Enseignement et la Recherche(2011)
Subjects: local density of states, molecular beam epitaxy, charge ordering, scanning tunneling spectroscopy, [PHYS.COND.CM-SCE]Physics [physics]/Condensed Matter [cond-mat]/Strongly Correlated Electrons [cond-mat.str-el], 2D materials, correlated materials, [PHYS.COND.CM-MSQHE]Physics [physics]/Condensed Matter [cond-mat]/Mesoscopic Systems and Quantum Hall Effect [cond-mat.mes-hall]
Abstract: International audience
Published: 2023
Full Text: View/download PDF

2. Sublattice dependence and gate-tunability of midgap and resonant states induced by native dopants in Bernal-stacked bilayer graphene

Author: François Ducastelle, Eberth A. Quezada-Lopez, Jairo Velasco, C. Bena, Frédéric Joucken, Zhehao Ge, Kenji Watanabe, Takashi Tanagushi, University of California [Santa Cruz] (UCSC), University of California, Arizona State University [Tempe] (ASU), Institut de Physique Théorique - UMR CNRS 3681 (IPHT), Centre National de la Recherche Scientifique (CNRS)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), LEM, UMR 104, CNRS-ONERA, Université Paris-Saclay (Laboratoire d'étude des microstructures), ONERA-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), DMAS, ONERA, Université Paris Saclay [Châtillon], ONERA-Université Paris-Saclay, National Institute for Materials Science (NIMS), J. V. J. acknowledges support from the National Science Foundation under Grant No. DMR-1753367 and the Army Research Office under Contract No. W911NF-17-1-0473. K. W. and T. T. acknowledge support from the Elemental Strategy Initiative conducted by the MEXT, Japan, Grant No. JPMXP0112101001 and JSPS KAKENHI Grant No. JP20H00354., University of California [Santa Cruz] (UC Santa Cruz), University of California (UC), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)
Subjects: Materials science, Band gap, FOS: Physical sciences, General Physics and Astronomy, Tight-binding model, 02 engineering and technology, Local density of states, 01 natural sciences, law.invention, Condensed Matter::Materials Science, [SPI]Engineering Sciences [physics], Tight binding, Dopants, law, Condensed Matter::Superconductivity, Mesoscale and Nanoscale Physics (cond-mat.mes-hall), 0103 physical sciences, Physics::Atomic and Molecular Clusters, [CHIM]Chemical Sciences, 010306 general physics, Scanning tunneling microscopy, [PHYS]Physics [physics], Condensed Matter - Materials Science, Valence (chemistry), Condensed matter physics, Dopant, Condensed Matter - Mesoscale and Nanoscale Physics, Graphene, Materials Science (cond-mat.mtrl-sci), 021001 nanoscience & nanotechnology, 3. Good health, Scanning tunneling microscope, 0210 nano-technology, Bilayer graphene
Abstract: The properties of semiconductors can be crucially impacted by midgap states induced by dopants, which can be native or intentionally incorporated in the crystal lattice. For Bernal-stacked bilayer graphene (BLG), which has a tunable bandgap, the existence of midgap states induced by dopants has been conjectured, but never confirmed experimentally. Here, we report scanning tunneling microscopy and spectroscopy results, supported by tight-binding calculations, that demonstrate the existence of midgap states in BLG. We show that the midgap state in BLG -- for which we demonstrate gate-tunability -- appears when the dopant is hosted on the non-dimer sublattice sites. We further evidence the presence of narrow resonances at the onset of the high energy bands (valence or conduction, depending on the dopant type) when the dopants lie on the dimer sublattice sites. These results suggest that dopants/defects can play an important role in the transport and optical properties of multilayer graphene samples, especially at energies close to the band extrema., Includes supplementary material
Published: 2021
Full Text: View/download PDF

3. Electronic properties of atomically coherent square PbSe nanocrystal superlattice resolved by Scanning Tunneling Spectroscopy

Author: Capiod, Pierre, Van Der Sluijs, Maaike, De Boer, Jeroen, Delerue, Christophe, Swart, Ingmar, Vanmaekelbergh, Daniel, Sub Condensed Matter and Interfaces, Condensed Matter and Interfaces, Debye Institute for Nanomaterials Science, Utrecht University [Utrecht], Physique - IEMN (PHYSIQUE - IEMN), Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 (IEMN), Centrale Lille-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF)-JUNIA (JUNIA), Université catholique de Lille (UCL)-Université catholique de Lille (UCL)-Centrale Lille-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF)-JUNIA (JUNIA), Université catholique de Lille (UCL)-Université catholique de Lille (UCL), European Project: FIRST STEP, Sub Condensed Matter and Interfaces, Condensed Matter and Interfaces, and Centrale Lille-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF)-JUNIA (JUNIA)-Centrale Lille-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF)-JUNIA (JUNIA)
Subjects: Materials science, Band gap, Superlattice, Scanning tunneling spectroscopy, Bioengineering, 02 engineering and technology, semiconductors, 010402 general chemistry, 01 natural sciences, materials, law.invention, chemistry.chemical_compound, Condensed Matter::Materials Science, law, Taverne, General Materials Science, Electrical and Electronic Engineering, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], Spectroscopy, Electronic band structure, Lead selenide, 2D, Scanning Tunneling Spectroscopy, Local density of states, Condensed matter physics, Mechanical Engineering, 2D, materials, General Chemistry, 021001 nanoscience & nanotechnology, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, 0104 chemical sciences, chemistry, Mechanics of Materials, nanocrystal superlattices, scanning tunneling microscopy, Scanning tunneling microscope, 0210 nano-technology
Abstract: International audience; Rock-salt lead selenide nanocrystals can be used as building blocks for large scale square superlattices via two-dimensional assembly of nanocrystals at a liquid-air interface followed by oriented attachment. Here we report Scanning Tunneling Spectroscopy (STS) measurements of the local density of states of an atomically coherent superlattice with square geometry made from PbSe nanocrystals. Controlled annealing of the sample permits the imaging of a clean structure and to reproducibly probe the band gap and the valence hole and conduction electron states. The measured band gap and peak positions are compared to the results of optical spectroscopy and atomistic tight-binding calculations of the square superlattice band Electronic properties of atomically coherent square PbSe nanocrystal superlattice resolved by Scanning Tunne structure. In spite of the crystalline connections between nanocrystals that induce significant electronic couplings, the electronic structure of the superlattices remains very strongly influenced by the effects of disorder and variability.
Published: 2021
Full Text: View/download PDF

4. Some Remarks on Spectral Averaging and the Local Density of States for Random Schrödinger Operators on $L^2 (\mathbb {R}^d)$

Author: Peter D. Hislop, Jean Michel Combes, Centre de Physique Théorique - UMR 7332 (CPT), Aix Marseille Université (AMU)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS), CPT - E8 Dynamique quantique et analyse spectrale, and Aix Marseille Université (AMU)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Pure mathematics, Trace (linear algebra), Local density of states, [PHYS.MPHY]Physics [physics]/Mathematical Physics [math-ph], Perturbation theory (quantum mechanics), Function (mathematics), Limit (mathematics), Lambda, Lipschitz continuity, Constant (mathematics), ComputingMilieux_MISCELLANEOUS, Mathematics
Abstract: We prove some local estimates on the trace of spectral projectors for random Schrodinger operators restricted to cubes $\Lambda \subset \mathbb {R}^d$. We also present a new proof of the spectral averaging result based on analytic perturbation theory. Together, these provide another proof of the Wegner estimate with an explicit form of the constant and an alternate proof of the Birman-Solomyak formula. We also use these results to prove the Lipschitz continuity of the local density of states function for a restricted family of random Schrodinger operators on cubes $\Lambda \subset \mathbb {R}^d$, for $d \geqslant 1$. The result holds for low energies without a localization assumption but is not strong enough to extend to the infinite-volume limit.
Published: 2021
Full Text: View/download PDF

5. Optical polarization analogue in free electrons beams

Author: Hugo Lourenço-Martins, Davy Gérard, Mathieu Kociak, Laboratoire de Physique des Solides (LPS), Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Lumière, nanomatériaux et nanotechnologies (L2n), Université de Technologie de Troyes (UTT)-Centre National de la Recherche Scientifique (CNRS), ANR-17-CE24-0039,2D-CHIRAL,Controle de la polarisation des vallées dans des dichalcogénures 2D par nanostructures plasmoniques chirales(2017), ANR-10-EQPX-0050,TEMPOS,Microscopie electronique en transmission sur le plateau Palaiseau Orsay Saclay(2010), European Project: 823717,ESTEEM3, Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11), and Université de Technologie de Troyes (UTT)
Subjects: Free electron model, Physics, [PHYS]Physics [physics], Physics - Instrumentation and Detectors, Local density of states, Electron energy loss spectroscopy, FOS: Physical sciences, General Physics and Astronomy, Optical polarization, Instrumentation and Detectors (physics.ins-det), Electron, Polarization (waves), 01 natural sciences, 010305 fluids & plasmas, Condensed Matter - Other Condensed Matter, Dipole, 0103 physical sciences, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, Atomic physics, 010306 general physics, Circular polarization, Optics (physics.optics), Other Condensed Matter (cond-mat.other), Physics - Optics
Abstract: Spectromicroscopy techniques with fast electrons can quantitatively measure the optical response of excitations with unrivalled spatial resolution. However, owing to their inherently scalar nature, electron waves cannot access the polarization-related quantities. Despite promising attempts based on the conversion of concepts originating from singular optics (such as vortex beams), the definition of an optical polarization analogue for fast electrons has remained an open question. Here we establish such an analogue using the dipole transition vector of the electron between two well-chosen singular wave states. We show that electron energy loss spectroscopy allows the direct measurement of the polarized electromagnetic local density of states. In particular, in the case of circular polarization, it directly measures the local optical spin density. This work establishes electron energy loss spectroscopy as a quantitative technique to tackle fundamental issues in nano-optics, such as super-chirality, local polarization of dark excitations or polarization singularities at the nanoscale. The functionality of electron energy loss spectroscopy can be extended to include a polarization analogue constructed via the dipole transition vector between two electronic states, bringing it closer to its optical counterpart.
Published: 2021
Full Text: View/download PDF

6. Upconverter Nanoparticles as Plasmon-induced Broadband Light Converters

Author: Vallée, Renaud, Léon, Arthur, Centre de Recherche Paul Pascal (CRPP), and Université de Bordeaux (UB)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Range (particle radiation), Materials science, Local density of states, Field (physics), business.industry, Plasmonic Array, FDTD, Finite-difference time-domain method, General Medicine, 7. Clean energy, Spectral line, [SPI.MAT]Engineering Sciences [physics]/Materials, Upconverters, Gap Mode Resonance, Optoelectronics, business, Quantum, Plasmon, Excitation
Abstract: International audience; We show numerically how lanthanide-doped upconverter nanocrystals inserted at optimal positions in adjustable and smooth 2D plasmonic arrays may change and potentially control the whole UV-visible-NIR reflectance spectra displayed by these structures. The analysis and interplay between a custom-built simple 5-levels 2-electrons quantum model and the bare structure have been studied in depth and revealed very fundamental and interesting physics. Essentially, the largely and selectively enhanced white-light excitation field and optimized local density of states at the location of the emitters favor some energy transfer paths and a redistribution of light energy in a broad spectral range. Interestingly, the extent to which the spectra can be modulated owing to the emission properties of such very robust multilevel emitters may find interesting applications and notably allow increased efficiency of emission in Light Emitting Devices or solar light redistribution and collection in Solar cells, where conversions from one color to any other one play a major role.
Published: 2021
Full Text: View/download PDF

7. Differential reflectivity spectroscopy on single patch nanoantennas

Author: Juan Uriel Esparza, Rafael Salas-Montiel, Jean-Marc Frigerio, Bruno Gallas, Willy Daney de Marcillac, Amit Raj Dhawan, Agnès Maître, Institut des Nanosciences de Paris (INSP), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Lumière, nanomatériaux et nanotechnologies (L2n), Institut Charles Delaunay (ICD), and Université de Technologie de Troyes (UTT)-Centre National de la Recherche Scientifique (CNRS)-Université de Technologie de Troyes (UTT)-Centre National de la Recherche Scientifique (CNRS)
Subjects: 010302 applied physics, Electromagnetic field, Materials science, Local density of states, Physics and Astronomy (miscellaneous), business.industry, Surface plasmon, Physics::Optics, 02 engineering and technology, 021001 nanoscience & nanotechnology, 01 natural sciences, Ray, 0103 physical sciences, Optoelectronics, [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, 0210 nano-technology, Spectroscopy, Absorption (electromagnetic radiation), business, Plasmon, Visible spectrum
Abstract: International audience; We present an experimental technique adapted to characterize individual metallic nanostructures in terms of differential reflectivity spectroscopy. We analyze gold patch nanoantennas holding different morphological properties. Our experimental methodology shows steady and reliable results consistent with classical analytical approximations and simulation methods. This technique allows us to identify absorption properties of metallic nanostructures commonly associated with surface plasmon resonances. By contrasting the light absorbed solely by the metallic antenna with respect to a surrounding reference medium, we found that some antennas show absorption of almost 50% of the incident light across the range of the visible spectrum. Plasmonic patch nanoantennas are promising systems in which the confinement of the electromagnetic field inside the dielectric gap strongly modifies the local density of states.
Published: 2020
Full Text: View/download PDF

8. Spectroscopic evidence for strong correlations between local superconducting gap and local Altshuler-Aronov density of states suppression in ultrathin NbN films

Author: Mikhail A. Skvortsov, Mikhail Feigel'man, Konstantin Ilin, Tristan Cren, Dimitri Roditchev, François Debontridder, C. Brun, Michael Siegel, C. Carbillet, Lev Ioffe, Vasily S. Stolyarov, V. Cherkez, C. Noûs, Spectroscopie des nouveaux états quantiques (INSP-E2), Institut des Nanosciences de Paris (INSP), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), and Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Band gap, Scanning tunneling spectroscopy, FOS: Physical sciences, 02 engineering and technology, 01 natural sciences, Superconductivity (cond-mat.supr-con), symbols.namesake, Electrical resistivity and conductivity, Condensed Matter::Superconductivity, 0103 physical sciences, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], 010306 general physics, ComputingMilieux_MISCELLANEOUS, [PHYS.COND.CM-MSQHE]Physics [physics]/Condensed Matter [cond-mat]/Mesoscopic Systems and Quantum Hall Effect [cond-mat.mes-hall], Superconductivity, Physics, Local density of states, Condensed matter physics, Condensed Matter - Superconductivity, Fermi level, 021001 nanoscience & nanotechnology, [PHYS.COND.CM-S]Physics [physics]/Condensed Matter [cond-mat]/Superconductivity [cond-mat.supr-con], symbols, Density of states, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], [PHYS.COND.CM-SCE]Physics [physics]/Condensed Matter [cond-mat]/Strongly Correlated Electrons [cond-mat.str-el], 0210 nano-technology, Pseudogap
Abstract: Disorder has different profound effects on superconducting thin films. For a large variety of materials, increasing disorder reduces electronic screening which enhances electron-electron repulsion. These fermionic effects lead to a mechanism described by Finkelstein: when disorder combined to electron-electron interactions increases, there is a global decrease of the superconducting energy gap $\Delta$ and of the critical temperature $T_c$, the ratio $\Delta$/$k_BT_c$ remaining roughly constant. In addition, in most films an emergent granularity develops with increasing disorder and results in the formation of inhomogeneous superconducting puddles. These gap inhomogeneities are usually accompanied by the development of bosonic features: a pseudogap develops above the critical temperature $T_c$ and the energy gap $\Delta$ starts decoupling from $T_c$. Thus the mechanism(s) driving the appearance of these gap inhomogeneities could result from a complicated interplay between fermionic and bosonic effects. By studying the local electronic properties of a NbN film with scanning tunneling spectroscopy (STS) we show that the inhomogeneous spatial distribution of $\Delta$ is locally strongly correlated to a large depletion in the local density of states (LDOS) around the Fermi level, associated to the Altshuler-Aronov effect induced by strong electronic interactions. By modelling quantitatively the measured LDOS suppression, we show that the latter can be interpreted as local variations of the film resistivity. This local change in resistivity leads to a local variation of $\Delta$ through a local Finkelstein mechanism. Our analysis furnishes a purely fermionic scenario explaining quantitatively the emergent superconducting inhomogeneities, while the precise origin of the latter remained unclear up to now., Comment: 11 pages, 4 figures
Published: 2020
Full Text: View/download PDF

9. Electronic structure and quantum transport in twisted bilayer graphene with resonant scatterers

Author: Didier Mayou, Omid Faizy Namarvar, Ahmed Missaoui, Guy Trambly de Laissardière, Laurence Magaud, XLIM (XLIM), Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS), Université de Tunis El Manar (UTM), Systèmes hybrides de basse dimensionnalité (HYBRID), Institut Néel (NEEL), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA), Optique et Matériaux (OPTIMA), Laboratoire de Physique Théorique et Modélisation (LPTM - UMR 8089), and Centre National de la Recherche Scientifique (CNRS)-CY Cergy Paris Université (CY)
Subjects: Physics, [PHYS]Physics [physics], Local density of states, Condensed Matter - Mesoscale and Nanoscale Physics, Condensed matter physics, Scattering, Graphene, Bilayer, Stacking, FOS: Physical sciences, 02 engineering and technology, Electron, Electronic structure, 021001 nanoscience & nanotechnology, 01 natural sciences, law.invention, law, Mesoscale and Nanoscale Physics (cond-mat.mes-hall), 0103 physical sciences, 010306 general physics, 0210 nano-technology, Bilayer graphene
Abstract: Stacking layered materials revealed to be a very powerful method to tailor their electronic properties. It has indeed been theoretically and experimentally shown that twisted bilayers of graphene (tBLG) with a rotation angle $\ensuremath{\theta}$, forming a Moir\'e pattern, confine electrons in a tunable way as a function of $\ensuremath{\theta}$. Here, we study electronic structure and transport in tBLG using tight-binding numerical calculations in commensurate twisted bilayer structures and a pertubative continuous theory, which is valid for not-too-small angles ($\ensuremath{\theta}g\ensuremath{\sim}{2}^{\ensuremath{\circ}}$). These two approaches allow us to understand the effect of $\ensuremath{\theta}$ on the local density of states, the electron lifetime due to disorder, the DC conductivity, and the conductivity quantum correction due to multiple scattering effects. We distinguish the cases where disorder is equally distributed over two layers or only one layer. When only one layer is disordered, diffusion properties depend strongly on $\ensuremath{\theta}$, thus showing the effect of Moir\'e electronic localization at intermediate angles $\ensuremath{\theta}, \ensuremath{\sim}{2}^{\ensuremath{\circ}}l\ensuremath{\theta}l\ensuremath{\sim}{20}^{\ensuremath{\circ}}$.
Published: 2020
Full Text: View/download PDF

10. Probing the Radiative Electromagnetic Local Density of States in Nanostructures with a Scanning Tunneling Microscope

Author: Eric Le Moal, Javier Aizpurua, Mario Zapata-Herrera, Andrei G. Borisov, Elizabeth Boer-Duchemin, Sylvie Marguet, Mathieu Kociak, Gérald Dujardin, Shuiyan Cao, Alfredo Campos, Institut des Sciences Moléculaires d'Orsay (ISMO), Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Nanophysique et Surfaces, Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), China Scholarship Council, European Commission, Colciencias (Colombia), Institut des Sciences Moléculaires d'Orsay, Agence Nationale de la Recherche (France), Ministerio de Economía y Competitividad (España), Eusko Jaurlaritza, Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Nanjing University of Aeronautics and Astronautics (NUAA), Center of Materials Physics CSIC-UPV / EHU and Donostia International Physics Center, University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Laboratoire de Physique des Solides (LPS), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Edifices Nanométriques (LEDNA), Nanosciences et Innovation pour les Matériaux, la Biomédecine et l'Energie (ex SIS2M) (NIMBE UMR 3685), Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Donostia International Physics Center (DIPC), China Scholarship Council (CSC) (No. 201304910386), 'Colombian Administrative Department of Science, Technology and Innovation' - COLCIENCIAS under its 'Estancias Postdoctorales 784-2017' call, Conseil Régional, Île-de-France (DIM Nano-K), Project FIS2016-80174-P of the Spanish MICINN, project IT1164-19 of the Basque Government, ANR-12-BS10-0016,HAPPLE,Nanoemetteurs plasmoniques hybrides anisotropes(2012), European Project: 737093,FEMTOTERABYTE, Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut Rayonnement Matière de Saclay (IRAMIS), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)
Subjects: Materials science, Near and far field, 02 engineering and technology, 01 natural sciences, Molecular physics, law.invention, 010309 optics, Condensed Matter::Materials Science, law, Condensed Matter::Superconductivity, 0103 physical sciences, Radiative transfer, Emission spectrum, Electrical and Electronic Engineering, Spectroscopy, ComputingMilieux_MISCELLANEOUS, [PHYS]Physics [physics], Local density of states, Electron energy loss spectroscopy, [CHIM.MATE]Chemical Sciences/Material chemistry, 021001 nanoscience & nanotechnology, Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials, Light emission, Scanning tunneling microscope, 0210 nano-technology, Biotechnology
Abstract: A novel technique for the investigation of the radiative contribution to the electromagnetic local density of states is presented. The inelastic tunneling current from a scanning tunneling microscope (STM) is used to locally and electrically excite the plasmonic modes of a triangular gold platelet. The radiative decay of these modes is detected through the transparent substrate in the far field. Emission spectra, which depend on the position of the STM excitation, as well as energy-filtered emission maps for particular spectral windows are acquired using this technique. The STM-nanosource spectroscopy and microscopy results are compared to those obtained from spatially resolved electron energy loss spectroscopy (EELS) maps on similar platelets. While EELS is known to be related to the total projected electromagnetic local density of states, the light emission from the STM-nanosource is shown here to select the radiative contribution. Full electromagnetic calculations are carried out to explain the experimental STM data and provide valuable insight into the radiative nature of the different contributions of the breathing and edge plasmon modes of the nanoparticles. Our results introduce the STM-nanosource as a tool to investigate and engineer light emission at the nanoscale., S.C. acknowledges the financial support of the China Scholarship Council (CSC; No. 201304910386). M.Z.-H. acknowledges the financial support of the European Union under the Project H2020 FETOPEN-2016-2017 “FEMTOTERABYTE” (Project No. 737093) and the “Colombian Administrative Department of Science, Technology and Innovation” - COLCIENCIAS under its “Estancias Postdoctorales 784-2017” call. He also acknowledges the hospitality of the Institute des Sciences Moleculaires d’Orsay and Dr. Nuno de Sousa for his guidance and support using COMSOL Multiphysics. S.M. was supported by the HAPPLE grant (French National Research Agency: ANR-12-BS10-0016). This work is partially funded by the Conseil Regional, Ile-deFrance (DIM Nano-K). J.A. acknowledges Project FIS2016-80174-P of the Spanish MICINN and Project IT1164-19 of the Basque Government.
Published: 2020
Full Text: View/download PDF

11. Engineering a light–matter strong coupling regime in perovskite-based plasmonic metasurface: quasi-bound state in the continuum and exceptional points

Author: Hai Son Nguyen, Emmanuel Drouard, Leran Lu, Lydie Ferrier, Christian Seassal, Quynh Le-Van, INL - Nanophotonique (INL - Photonique), Institut des Nanotechnologies de Lyon (INL), École Centrale de Lyon (ECL), Université de Lyon-Université de Lyon-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-École supérieure de Chimie Physique Electronique de Lyon (CPE)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-École Centrale de Lyon (ECL), and Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Condensed Matter::Quantum Gases, Local density of states, Condensed matter physics, Condensed Matter::Other, Exciton, Surface plasmon, Physics::Optics, Position and momentum space, 02 engineering and technology, 021001 nanoscience & nanotechnology, 01 natural sciences, Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials, 010309 optics, Condensed Matter::Materials Science, 0103 physical sciences, Bound state, Polariton, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, Condensed Matter::Strongly Correlated Electrons, [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, 0210 nano-technology, Plasmon, Transformation optics
Abstract: We present theoretically the formation of exciton–photon polaritons and exciton-surface plasmon polaritons in a perovskite-based subwavelength lattice on the metallic plane. It is shown that the later polaritons will be achieved as the perovskite layer is ultra-thin ( < 50 nm ), while the co-existence of both polaritons will dominate, as the thickness of the perovskite metasurface approaches wavelength-scale. In the two cases, the lower polaritonic branches consist of dark and bright modes corresponding to infinite and finite radiative quality factors, respectively. Another salient property in this work is that it allows one to obtain exceptional points (EPs) in momentum space with a four-fold enhancement of local density of states through engineering the perovskite metasurface. Our findings show that the perovskite metasurface is an attractive and rich platform to make polaritonic devices, even with the presence of a lossy metallic layer.
Published: 2020
Full Text: View/download PDF

12. Understanding why Alite is responsible of the main mechanical characteristics in Portland cement

Author: M. Laanaiya, A. Bouibes, Ali Zaoui, Laboratoire de Génie Civil et Géo-Environnement (LGCgE) - ULR 4515 (LGCgE), Université d'Artois (UA)-Université de Lille-Ecole nationale supérieure Mines-Télécom Lille Douai (IMT Lille Douai), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-JUNIA (JUNIA), Université catholique de Lille (UCL)-Université catholique de Lille (UCL), and Université de Lille
Subjects: Alite, Local density of states, Materials science, [PHYS.PHYS.PHYS-ATOM-PH]Physics [physics]/Physics [physics]/Atomic Physics [physics.atom-ph], 0211 other engineering and technologies, Charge density, 02 engineering and technology, Building and Construction, Electronic structure, 021001 nanoscience & nanotechnology, Ion, [SPI.MAT]Engineering Sciences [physics]/Materials, chemistry.chemical_compound, [SPI.GCIV]Engineering Sciences [physics]/Civil Engineering, chemistry, [PHYS.QPHY]Physics [physics]/Quantum Physics [quant-ph], Chemical physics, 021105 building & construction, General Materials Science, Density functional theory, 0210 nano-technology, Anisotropy, Ground state, ComputingMilieux_MISCELLANEOUS
Abstract: We provide here a full analysis of the ground state properties of Tricalcium silicate Ca3SiO5 (C3S) by means of density functional theory. Elastic behaviour of C3S was characterized by considering the stable phase and anisotropy of this material. Moreover, the electronic structure is determined in order to get an insight into the reaction mechanism of C3S. Local density of states (LDOS) of valence band maximum (VBM) and conduction band minimum (CBM) are analysed to characterize reactive sites of C3S. Two oxygen atom-types were distinguished from the charge density of the system. LDOS of VBM is highly localized explaining the observed high reactivity of C3S under electrophilic attacks (e.g. H+). In addition, reactive sites under electrophilic attacks are noticed to be only around some specific oxygen atoms. In contrast, the analysis of LDOS for CBM suggests that some calcium atoms are responsible for undergoing reaction with anions such as hydroxide ion.
Published: 2019
Full Text: View/download PDF

13. A three dimensional numerical quantum mechanical model of field electron emission from metallic surfaces covered with carbon adsorbates

Author: Bruno Lepetit, Maykel Márquez-Mijares, Théorie (LCAR), Laboratoire Collisions Agrégats Réactivité (LCAR), Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3)
Subjects: 010302 applied physics, Local density of states, Materials science, Astrophysics::High Energy Astrophysical Phenomena, Plane wave, General Physics and Astronomy, 02 engineering and technology, 021001 nanoscience & nanotechnology, 01 natural sciences, Molecular physics, law.invention, [SPI.MAT]Engineering Sciences [physics]/Materials, Field electron emission, [SPI]Engineering Sciences [physics], 13. Climate action, law, Electric field, 0103 physical sciences, Density functional theory, Scanning tunneling microscope, 0210 nano-technology, Current density, Electronic density
Abstract: International audience; The effect of metallic surface contamination on field electron emission is investigated for the first time using a three dimensional quantum mechanical model. The plane wave periodic version of the density functional theory is used to obtain wavefunctions and potentials. Local and averaged emitted current densities are obtained from them using time dependent perturbation theory. This method is used to study the effect of the presence of carbon adsorbates on emission from tungsten surfaces. Fowler-Nordheim plots which provide the dependence of the emitted current with the external electric field show that carbon contamination inhibits emission. Significant differences with the results of the analytical Fowler-Nordheim model are observed. Emissions images (i. e. the spatial dependence of the emitted current density) are presented to identify the important emission spots. These images are significantly different from the electronic density plots usually presented to model constant height scanning tunnelling microscope images. Analysis of the emitted current density energy distributions in the light of the projected local density of states provides a deeper understanding of the emission process.
Published: 2019
Full Text: View/download PDF

14. Thickness limitation of band to band tunneling process in InGaAs/GaAsSb type-II tunnel junctions designed for multijunction solar cells

Author: Kevin Louarn, Inès Massiot, Alexandre Bounouh, François Piquemal, Nicolas Cavassilas, Yann Claveau, Ludovic Marigo-Lombart, Alexandre Arnoult, Chantal Fontaine, Guilhem Almuneau, Équipe Photonique (LAAS-PHOTO), Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT), Institut des Matériaux, de Microélectronique et des Nanosciences de Provence (IM2NP), Aix Marseille Université (AMU)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS), Service Techniques et Équipements Appliqués à la Microélectronique (LAAS-TEAM), Laboratoire National de Métrologie et d'Essais [Trappes] (LNE ), Laboratoire d'Intégration des Systèmes et des Technologies (LIST (CEA)), Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Équipe Photonique ( LAAS-PHOTO ), Laboratoire d'analyse et d'architecture des systèmes [Toulouse] ( LAAS ), Centre National de la Recherche Scientifique ( CNRS ) -Université Toulouse III - Paul Sabatier ( UPS ), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse ( INSA Toulouse ), Institut National des Sciences Appliquées ( INSA ) -Institut National des Sciences Appliquées ( INSA ) -Institut National Polytechnique [Toulouse] ( INP ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Toulouse III - Paul Sabatier ( UPS ), Institut National des Sciences Appliquées ( INSA ) -Institut National des Sciences Appliquées ( INSA ) -Institut National Polytechnique [Toulouse] ( INP ), Institut des Matériaux, de Microélectronique et des Nanosciences de Provence ( IM2NP ), Aix Marseille Université ( AMU ) -Université de Toulon ( UTLN ) -Centre National de la Recherche Scientifique ( CNRS ), Service Techniques et Équipements Appliqués à la Microélectronique ( LAAS-TEAM ), Laboratoire National de Métrologie et d'Essais [Trappes] ( LNE ), Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ), Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), and Laboratoire d'Intégration des Systèmes et des Technologies (LIST)
Subjects: Materials science, [ SPI.MAT ] Engineering Sciences [physics]/Materials, Energy Engineering and Power Technology, 02 engineering and technology, Multijunction photovoltaic cell, Computer Science::Computational Geometry, Epitaxy, 7. Clean energy, 01 natural sciences, [SPI.MAT]Engineering Sciences [physics]/Materials, Condensed Matter::Materials Science, Tunnel junction, Condensed Matter::Superconductivity, 0103 physical sciences, Materials Chemistry, Electrochemistry, Chemical Engineering (miscellaneous), Tunneling current, Electrical and Electronic Engineering, [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, Quantum tunnelling, 010302 applied physics, Local density of states, business.industry, [SPI.NRJ]Engineering Sciences [physics]/Electric power, Heterojunction, 021001 nanoscience & nanotechnology, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, Optoelectronics, [ SPI.NANO ] Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, [ SPI.OPTI ] Engineering Sciences [physics]/Optics / Photonic, 0210 nano-technology, business, Molecular beam epitaxy
Abstract: International audience; This article reports on the impact of the thickness and/or the composition on the performance of type-II n+ InGaAs/p+ GaAsSb tunnel junctions. The InGaAs/GaAsSb staggered band-offset heterojunction is expected to improve tunneling properties. Devices have been grown by molecular beam epitaxy with various thicknesses and/or Sb and In concentrations. For thin elastically strained type-II tunnel junctions, the electrical characteristics exhibit degraded transport performances compared to the reference p+ GaAs/n+ GaAs tunnel junction structures, while much better tunneling peak currents are achieved with strain-relaxed thick type-II tunnel junctions. Based on a theoretical analysis of the local density of states and the band-edges profiles of the type-II tunnel junctions, we propose a suitable design for type-II tunnel junctions with high tunneling current density toward their use in multi-junction solar cells.
Published: 2019
Full Text: View/download PDF

15. Multifractality at the Weyl-semimetal–diffusive-metal transition for generic disorder

Author: Andrei A. Fedorenko, David Carpentier, Eric Brillaux, Laboratoire de Physique de l'ENS Lyon (Phys-ENS), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), ANR-17-CE30-0023,DIRAC3D,Excitations de basse energie dans les semimétaux tridimensionnels de Dirac et de Weyl(2017), École normale supérieure - Lyon (ENS Lyon)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon
Subjects: Physics, Local density of states, Condensed matter physics, and partially ordered systems, Scalar (mathematics), Weyl semimetal, FOS: Physical sciences, 02 engineering and technology, Disordered Systems and Neural Networks (cond-mat.dis-nn), Renormalization group, Condensed Matter - Disordered Systems and Neural Networks, 021001 nanoscience & nanotechnology, 01 natural sciences, Condensed Matter::Disordered Systems and Neural Networks, Inhomogeneous, [PHYS.PHYS.PHYS-GEN-PH]Physics [physics]/Physics [physics]/General Physics [physics.gen-ph], Dispersion relation, 0103 physical sciences, disordered, 010306 general physics, 0210 nano-technology, Wave function, Scaling, Quantum
Abstract: A Weyl semimetal is a three dimensional topological gapless phase. In the presence of strong enough disorder it undergoes a quantum transition towards a diffusive metal phase whose universality class depends on the range of disorder correlations. Similar to other quantum transitions driven by disorder, the critical wave functions at the semimetal-diffusive metal transition exhibit multifractality. Using renormalization group methods we study the corresponding multifractal spectrum as a function of the range of disorder correlations for generic disorder including random scalar and vector potentials. We also discuss the relation between the geometric fluctuations of critical wave functions and the broad distribution of the local density of states (DOS) at the transition. We derive a new scaling relation for the typical local DOS and argue that it holds for other disorder-driven transitions in which both the average and typical local DOS vanish on one side of the transition. As an illustration we apply it to the recently discussed unconventional quantum transition in disordered semiconductors with power-law dispersion relation near the band edge., Comment: 11 pages, 4 figures
Published: 2019
Full Text: View/download PDF

16. Electronic properties of Pb islands on graphene: Consequences of a weak interface coupling from a combined STM and ab initio study

Author: Pierre Mallet, Jean-Yves Veuillen, Laurence Magaud, T. Le Quang, V. Cherkez, Nano-Electronique Quantique et Spectroscopie (QuNES), Institut Néel (NEEL), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Systèmes hybrides de basse dimensionnalité (HYBRID), GENCI Grant, ANR-15-CE24-0017,J2D,Jonctions ultrafines réalisées par empilement de matériaux 2D: nouveaux constituents de base pour l'électronique(2015), and ANR-15-GRFL-0004,HiMagGraphene,Atomic-scale control of graphene magnetism using hydrogen atoms(2015)
Subjects: Materials science, Local density of states, Condensed matter physics, Graphene, Ab initio, 02 engineering and technology, Electronic structure, 021001 nanoscience & nanotechnology, 01 natural sciences, law.invention, law, Ab initio quantum chemistry methods, 0103 physical sciences, Monolayer, Proximity effect (superconductivity), [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Scanning tunneling microscope, 010306 general physics, 0210 nano-technology
Abstract: International audience; By means of scanning tunneling microscopy and spectroscopy, we investigate the electronic properties oflead islands (width 5–100 nm, thickness 5–25 monolayers) deposited by molecular beam epitaxy on twistedgraphene layers grown on SiC(000-1). We find that elastic scattering processes govern the local density ofstates probed at the surface of the Pb islands, inducing (i) the well-known quantum well states due to electronconfinement in the direction perpendicular to the surface and (ii) spatial in-plane periodic modulations relatedto quasiparticle interferences off the island edges. Through a quantitative analysis of these effects, comparedwith ab initio calculations for a two-dimensional Pb slab, we conclude that the lead islands grown on the surfaceof graphene can be considered as freestanding from the point of view of their electronic structure, leaving thesurrounding graphene layer unperturbed. Accordingly, low bias tunneling spectra show evidence of a sizableinterface resistance. Nevertheless, we suggest that the transparency of the interface, which can be estimated fromits resistance, is good enough to induce superconductivity within the underlying graphene layer by proximityeffect with the Pb islands.
Published: 2018
Full Text: View/download PDF

17. Optical chirality density and flux measured in the local density of states of spiral plasmonic structures

Author: Airong Zhao, Aline Pham, Aurélien Drezet, Cyriaque Genet, Nano-Optique et Forces (NOF ), Institut Néel (NEEL), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Institut de Science et d'ingénierie supramoléculaires (ISIS), Réseau nanophotonique et optique, Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Matériaux et nanosciences d'Alsace (FMNGE), and Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)
Subjects: Physics, [PHYS]Physics [physics], Local density of states, Field (physics), High Energy Physics::Lattice, High Energy Physics::Phenomenology, Surface plasmon, Enantioselective synthesis, Physics::Optics, 02 engineering and technology, 021001 nanoscience & nanotechnology, 01 natural sciences, Molecular physics, 0103 physical sciences, Enantiomer, 010306 general physics, 0210 nano-technology, Chirality (chemistry), Plasmon, Circular polarization, ComputingMilieux_MISCELLANEOUS
Abstract: Efforts to improve enantioselective detection of chiral molecules have initiated great interest in the fields of chiral light and chiral plasmonics. While superchiral light had been reported as highly sensitive enantiomer probes, optical response of chiral molecules can also be boosted at the vicinity of chiral plasmonic structures due to enhanced light-molecule coupling. Here, we apply the fundamental description of chiral light, known as the chirality density and flux, to the local density of states (LDOS) which rules the processes of light-matter interactions. In spiral plasmonic structures, we experimentally demonstrate the mapping of far-field chiral LDOS properties by means of polarimetry analysis. We establish the link between the degree of circular polarization of freely propagating cavity modes and the chirality density and flux. Using the reciprocity theorem, we show that this measure can be used to probe to the near-field chirality associated with surface plasmon field. By mapping the chiral features of the LDOS, we report a helpful method for guiding the design of superchiral light and for the investigation of chiral light-matter interactions, opening doors to improved chiral molecular sensing.
Published: 2018
Full Text: View/download PDF

18. Attractive interaction between interstitial solutes and screw dislocations in bcc iron from first principles

Author: B. Lüthi, Francois Willaime, Lisa Ventelon, David Rodney, Service de recherches de métallurgie physique (SRMP), Département des Matériaux pour le Nucléaire (DMN), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Institut Lumière Matière [Villeurbanne] (ILM), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), ANR-16-CE08-0008,DeGAS,Glissement des dislocations dans les alliages : couplage chimie/microstructure(2016), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon
Subjects: Materials science, General Computer Science, General Physics and Astronomy, 02 engineering and technology, Plasticity, DFT calculations, 01 natural sciences, Condensed Matter::Materials Science, [SPI]Engineering Sciences [physics], Ab initio quantum chemistry methods, 0103 physical sciences, [CHIM]Chemical Sciences, General Materials Science, 010306 general physics, ComputingMilieux_MISCELLANEOUS, Line (formation), [PHYS]Physics [physics], Local density of states, Bcc iron, Dislocation-solute interaction, General Chemistry, Interaction energy, 021001 nanoscience & nanotechnology, Core (optical fiber), Computational Mathematics, Octahedron, Mechanics of Materials, Chemical physics, Dislocation, 0210 nano-technology
Abstract: Plasticity in steels depends largely on how dislocations interact with solute atoms. We consider here typical interstitial solutes (B, C, N, O) in body-centered cubic (bcc) Fe and show using ab initio calculations that, systematically, when a row of interstitial solutes is in the vicinity of a 1 / 2 〈 1 1 1 〉 screw dislocation, the dislocation adopts a hard core, forming regular prisms of Fe atoms centered on the solute atoms. This low-energy configuration, previously known only for C atoms, induces attractive dislocation-solute interaction energies ranging from −1.3 to −0.2 eV, depending on the nature of the solutes and their separation distance along the dislocation line. This attractive reconstruction is explained by the larger Voronoi volume of the prismatic sites in the dislocation core compared to bulk octahedral sites. Moreover, an analysis of the local density of states gives a first insight into the chemical contribution responsible for the solute dependence of the interaction energy.
Published: 2018
Full Text: View/download PDF

19. Hyperbolic metamaterials based on metal-dielectric thin layers

Author: Ivan Voznyuk, Redha Abdeddaim, Jérôme Wenger, Elena Mikheeva, Fabien Lemarchand, Stefan Enoch, Julien Lumeau, Antonin Moreau, Institut FRESNEL (FRESNEL), Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Aix Marseille Université (AMU), CLARTE (CLARTE), Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Aix Marseille Université (AMU), RCMO (RCMO), HIPE (HIPE), Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS), Multiwave Innovat SAS, and Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], Local density of states, Thin layers, Materials science, [PHYS.PHYS]Physics [physics]/Physics [physics], business.industry, Physics::Optics, Metamaterial, Fluorescence correlation spectroscopy, 02 engineering and technology, 021001 nanoscience & nanotechnology, 01 natural sciences, Focused ion beam, Photon counting, 010309 optics, 0103 physical sciences, Optoelectronics, Spontaneous emission, 0210 nano-technology, business, Plasmon, ComputingMilieux_MISCELLANEOUS
Abstract: Metamaterials are artificial structures consisting of periodic sub-wavelength elements, they produce a particular electromagnetic response which often cannot be obtained from conventional media. One class of metamaterials called hyperbolic metamaterials (HMM) is widely studied nowadays due to their various applications such as subwavelength imaging and local density of states engineering. 1 In this work, HMM consisting of alternating gold, copper, and niobium pentoxide layers was designed and fabricated with plasma assisted electron beam deposition technique. For the accurate description of this material opto-geometrical parameters of thin layers composing it were determined separately using reflection and transmission measurements. Afterward, the produced material was structured using focused ion beam milling and its influence on the Alexa Fluor 647 biomolecules spontaneous emission was studied experimentally with fluorescence correlation spectroscopy and time-correlated single photon counting techniques. Combining these techniques enable the measurement of the fluorescence lifetime reduction together with the brightness enhancement per molecule. The same measurements were previously done for the structured gold films 3 which let us compare the results. HMM has shown significant emission enhancement compatible with the one produced by a single gold aperture which is known for its good plasmonic properties.
Published: 2018
Full Text: View/download PDF

20. Dynamical photo-induced electronic properties of molecular junctions

Author: Fabienne Michelini, Nicolas Cavassilas, Katawoura Beltako, Laurent Raymond, Institut des Matériaux, de Microélectronique et des Nanosciences de Provence (IM2NP), Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), and Aix Marseille Université (AMU)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Materials science, General Physics and Astronomy, FOS: Physical sciences, 02 engineering and technology, 01 natural sciences, 0103 physical sciences, Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Molecular orbital, Physical and Theoretical Chemistry, [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, 010306 general physics, Spectroscopy, Quantum tunnelling, ComputingMilieux_MISCELLANEOUS, Photocurrent, Local density of states, Condensed Matter - Mesoscale and Nanoscale Physics, business.industry, Molecular electronics, 021001 nanoscience & nanotechnology, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, Nanoelectronics, Femtosecond, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, Optoelectronics, 0210 nano-technology, business
Abstract: Nanoscale molecular-electronic devices and machines are emerging as promising functional elements, naturally flexible and efficient, for next-generation technologies. A deeper understanding of carrier dynamics in molecular junctions is expected to benefit many fields of nanoelectronics and power devices. We determine time-resolved charge current flowing at the donor-acceptor interface in molecular junctions connected to metallic electrodes by means of quantum transport simulations. The current is induced by the interaction of the donor with a Gaussian-shape femtosecond laser pulse. Effects of the molecular internal coupling, metal-molecule tunneling, and light-donor coupling on photocurrent are discussed. We then define the time-resolved local density of states which is proposed as an efficient tool to describe the absorbing molecule in contact with metallic electrodes. Non-equilibrium reorganization of hybridized molecular orbitals through the light-donor interaction gives rise to two phenomena: the dynamical Rabi shift and the appearance of Floquet-like states. Such insights into the dynamical photoelectronic structure of molecules are of strong interest for ultrafast spectroscopy and open avenues toward the possibility of analyzing and controlling the internal properties of quantum nanodevices with pump-push photocurrent spectroscopy.
Published: 2018
Full Text: View/download PDF

21. Coupling a single solid-state quantum emitter to an array of resonant plasmonic antennas

Author: Oliver G. Schmidt, Armando Rastelli, Paola Atkinson, Klas Lindfors, Harald Giessen, Markus Lippitz, Markus Pfeiffer, Universität zu Köln = University of Cologne, Max-Planck-Institut für Festkörperforschung, Max-Planck-Gesellschaft, Baden-Wuerttemberg Cooperative State University Stuttgart (DHBW Stuttgart), Institut de Biologie Paris Seine (IBPS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Leibniz Institute for Solid State and Materials Research (IFW Dresden), Leibniz Association, Universität Stuttgart [Stuttgart], Universität Bayreuth, HAL UPMC, Gestionnaire, and Universität zu Köln
Subjects: [PHYS.PHYS.PHYS-OPTICS] Physics [physics]/Physics [physics]/Optics [physics.optics], lcsh:Medicine, Physics::Optics, 02 engineering and technology, Optical field, 01 natural sciences, 7. Clean energy, Article, Position (vector), 0103 physical sciences, lcsh:Science, 010306 general physics, Absorption (electromagnetic radiation), Plasmon, Common emitter, Coupling, Physics, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], Multidisciplinary, Local density of states, business.industry, lcsh:R, 021001 nanoscience & nanotechnology, Optoelectronics, Physics::Accelerator Physics, lcsh:Q, Antenna (radio), 0210 nano-technology, business
Abstract: Plasmon resonant arrays or meta-surfaces shape both the incoming optical field and the local density of states for emission processes. They provide large regions of enhanced emission from emitters and greater design flexibility than single nanoantennas. This makes them of great interest for engineering optical absorption and emission. Here we study the coupling of a single quantum emitter, a self-assembled semiconductor quantum dot, to a plasmonic meta-surface. We investigate the influence of the spectral properties of the nanoantennas and the position of the emitter in the unit cell of the structure. We observe a resonant enhancement due to emitter-array coupling in the far-field regime and find a clear difference from the interaction of an emitter with a single antenna.
Published: 2018
Full Text: View/download PDF

22. Description of spontaneous photon emission and local density of states in the presence of a lossy polaritonic inhomogeneous medium

Author: Aurélien Drezet, Nano-Optique et Forces (NOF ), Institut Néel (NEEL), and Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])
Subjects: Physics, [PHYS]Physics [physics], Quantum Physics, Local density of states, Unitarity, business.industry, Physics::Optics, 02 engineering and technology, 021001 nanoscience & nanotechnology, 01 natural sciences, Noise (electronics), Quantum evolution, Quantum mechanics, 0103 physical sciences, Dissipative system, Spontaneous emission, Photonics, 010306 general physics, 0210 nano-technology, business, Plasmon, ComputingMilieux_MISCELLANEOUS
Abstract: We provide a description of spontaneous emission in a dispersive and dissipative linear inhomogeneous medium based on the generalized Huttner-Barnett model [Phys. Rev. A 46, 4306 (1992)]. Our discussion considers on an equal footing both the photonic and material fluctuations which are necessary to preserve unitarity of the quantum evolution. Within this approach we justify the results obtained in the past using the Langevin noise method that neglects the removal of photonic fluctuations. We finally discuss the concept of local density of states (LDOS) in a lossy and dispersive inhomogeneous environment that provides a basis for theoretical studies of fluorescent emitters near plasmonic and polaritonic antennas., Comment: Submitted : comments are welcome
Published: 2017
Full Text: View/download PDF

23. Near-field hyperspectral quantum probing of multimodal plasmonic resonators

Author: Aurélien Drezet, Martin Berthel, Erik Dujardin, Upkar Kumar, Aurélien Cuche, Christian Girard, Serge Huant, G. Colas des Francs, Centre d'élaboration de matériaux et d'études structurales (CEMES), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie de Toulouse (ICT-FR 2599), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA), Nano-Optique et Forces (NOF ), Institut Néel (NEEL), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Laboratoire Interdisciplinaire Carnot de Bourgogne (LICB), Université de Bourgogne (UB)-Centre National de la Recherche Scientifique (CNRS), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Nano-Optique et Forces (NEEL - NOF), Laboratoire Interdisciplinaire Carnot de Bourgogne (ICB), Centre d'élaboration de matériaux et d'études structurales ( CEMES ), Institut National des Sciences Appliquées - Toulouse ( INSA Toulouse ), Institut National des Sciences Appliquées ( INSA ) -Institut National des Sciences Appliquées ( INSA ) -Université Paul Sabatier - Toulouse 3 ( UPS ) -Centre National de la Recherche Scientifique ( CNRS ), NOF - Nano-Optique et Forces, Institut Néel ( NEEL ), Centre National de la Recherche Scientifique ( CNRS ) -Université Grenoble Alpes [Saint Martin d'Hères]-Centre National de la Recherche Scientifique ( CNRS ) -Université Grenoble Alpes [Saint Martin d'Hères], Laboratoire Interdisciplinaire Carnot de Bourgogne ( LICB ), and Université de Bourgogne ( UB ) -Centre National de la Recherche Scientifique ( CNRS )
Subjects: Physics, Photon, Local density of states, business.industry, Physics::Optics, Near and far field, 02 engineering and technology, [ PHYS.COND.CM-GEN ] Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], 021001 nanoscience & nanotechnology, 01 natural sciences, 010309 optics, Resonator, Excited state, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], 0103 physical sciences, Optoelectronics, Emission spectrum, Photonics, 0210 nano-technology, business, Plasmon
Abstract: International audience; Quantum systems, excited by an external source of photons, display a photodynamics that is ruled by a subtle balance between radiative or nonradiative energy channels when interacting with metallic nanostructures. We apply and generalize this concept to achieve a quantum probing of multimodal plasmonic resonators by collecting and filtering the broad emission spectra generated by a nanodiamond (ND) hosting a small set of nitrogen-vacancy (NV) color centers attached at the apex of an optical tip. Spatially and spectrally resolved information on the photonic local density of states (ph-LDOS) can be recorded with this technique in the immediate vicinity of plasmonic resonators, paving the way for a complete near-field optical characterization of any kind of nanoresonators in the single photon regime.
Published: 2017
Full Text: View/download PDF

24. Directional Local Density of States of Classical and Quantum Propagating Surface Plasmons

Author: Cyriaque Genet, Joel Bellessa, Martin Berthel, Serge Huant, Aurélien Drezet, Aline Pham, Quanbo Jiang, Nano-Optique et Forces (NOF ), Institut Néel (NEEL), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Institut Lumière Matière [Villeurbanne] (ILM), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Institut de Science et d'ingénierie supramoléculaires (ISIS), and Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)
Subjects: Physics, Local density of states, Surface plasmon, General Physics and Astronomy, Physics::Optics, 02 engineering and technology, Filter (signal processing), 021001 nanoscience & nanotechnology, 7. Clean energy, 01 natural sciences, Signal, Collimated light, Quantum mechanics, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], 0103 physical sciences, Coupling efficiency, 010306 general physics, 0210 nano-technology, Quantum, Electronic circuit
Abstract: International audience; We theoretically and experimentally introduce the concept of the local density of states (LDOS) associated with propagative surface plasmons (PSPs) launched along a structured thin gold film (a concept we call PSP LDOS). The alternative method couples a near-field optical microscope, in either the classical or the quantum regime of excitation, to a far-field leakage-radiation microscope. This method allows for selecting and collecting a very narrow portion of the directional SP wave vectors, thereby offering sufficient resolution to probe the collimation efficiency of a SP beam for a source near the focal point of a Bragg parabolic reflector. We are able to build and image the PSP LDOS in a fully integrated quantum SP launcher by depositing a diamond nanocrystal hosting nitrogen-vacancy centers at the focal point of the mirror. Our demonstration of the PSP LDOS with quantized SPs offers alternative prospects in the field of quantum plasmonics.
Published: 2017
Full Text: View/download PDF

25. Incommensurate charge ordered states in the t–t'–J model

Author: Peayush Choubey, Ting-Kuo Lee, Peter Hirschfeld, Wei-Lin Tu, Department of Physics [Gainesville] (UF|Physics), University of Florida [Gainesville] (UF), National Taiwan University, Academia Sinica, Fermions Fortement Corrélés (LPT) (FFC), Laboratoire de Physique Théorique (LPT), Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse)
Subjects: Superconductivity, Physics, Wannier function, Local density of states, Condensed matter physics, General Physics and Astronomy, 02 engineering and technology, 021001 nanoscience & nanotechnology, 01 natural sciences, law.invention, [PHYS.COND.CM-S]Physics [physics]/Condensed Matter [cond-mat]/Superconductivity [cond-mat.supr-con], Amplitude, Mean field theory, law, Condensed Matter::Superconductivity, Pairing, 0103 physical sciences, Scanning tunneling microscope, 010306 general physics, 0210 nano-technology, Charge density wave, ComputingMilieux_MISCELLANEOUS
Abstract: We study the incommensurate charge ordered states in the $\mathit{t-t^{\prime}-J}$ model using the Gutzwiller mean field theory on large systems. In particular, we explore the properties of incommensurate charge modulated states referred to as nodal pair density waves (nPDW) in the literature. nPDW states intertwine site and bond charge order with modulated $d$-wave pair order, and are characterized by a nonzero amplitude of uniform pairing; they also manifest a dominant intra-unit cell $d$-density wave form factor. To compare with a recent scanning tunneling microscopy (STM) study [Hamidian \textit{et al.}, Nat. Phys. 3519 (2015)] of the cuprate superconductor BSCCO-2212, we compute the continuum local density of states (LDOS) at a typical STM tip height using the Wannier function based approach. By Fourier transforming Cu and O sub-lattice LDOS we also obtain bias-dependent intra-unit cell form factors and spatial phase difference. We find that in the nPDW state the behavior of form factors and spatial phase difference as a function of energy agrees remarkably well with the experiment. This is in contrast to commensurate charge modulated states, which we show do not agree with experiment. We propose that the nPDW states are good candidates for the charge density wave phase observed in the superconducting state of underdoped cuprates.
Published: 2017
Full Text: View/download PDF

26. Asymptotic behavior of impurity-induced bound states in low-dimensional topological superconductors

Author: Cristina Bena, Vardan Kaladzhyan, Pascal Simon, Institut de Physique Théorique - UMR CNRS 3681 (IPHT), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique des Solides (LPS), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), ANR-06-TLOG-0001,MISTRAL,Plate-forme OpenSource pour l'authentification biométrique(2006), and Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11)
Subjects: FOS: Physical sciences, 02 engineering and technology, 01 natural sciences, Superconductivity (cond-mat.supr-con), Impurity, Condensed Matter::Superconductivity, 0103 physical sciences, Bound state, General Materials Science, Singlet state, Spatial dependence, 010306 general physics, Superconductivity, Physics, Local density of states, localized impurity, Condensed matter physics, Spin polarization, Condensed Matter - Superconductivity, 021001 nanoscience & nanotechnology, Condensed Matter Physics, [PHYS.COND.CM-S]Physics [physics]/Condensed Matter [cond-mat]/Superconductivity [cond-mat.supr-con], Shiba states, Pairing, unconventional superconductor, 0210 nano-technology
Abstract: We study theoretically the asymptotic behavior of the Shiba bound states associated with magnetic impurities embedded in both 2D and 1D anomalous superconductors. We calculate analytically the spatial dependence of the local density of states together with the spin polarization associated with the Shiba bound states. We show that the latter quantity exhibits drastic differences between s-wave and different types of p-wave superconductors. Such properties, which could be measured using spin-polarized STM, offer therefore a way to discriminate between singlet and triplet pairing in low-dimensional superconductors, as well as a way to estimate the amplitude of the triplet pairing in these systems., Comment: 18 pages, 5 figures
Published: 2016
Full Text: View/download PDF

27. Chiral optical local density of states in a spiral plasmonic cavity

Author: Aurélien Drezet, Aline Pham, Cyriaque Genet, Serge Huant, Quanbo Jiang, Joel Bellessa, Martin Berthel, Nano-Optique et Forces (NOF ), Institut Néel (NEEL), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Institut Lumière Matière [Villeurbanne] (ILM), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Institut de Science et d'ingénierie supramoléculaires (ISIS), and Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)
Subjects: Physics, Quantum Physics, Local density of states, Condensed matter physics, Condensed Matter - Mesoscale and Nanoscale Physics, FOS: Physical sciences, Physics::Optics, 02 engineering and technology, 021001 nanoscience & nanotechnology, 01 natural sciences, law.invention, Optical microscope, law, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], Mesoscale and Nanoscale Physics (cond-mat.mes-hall), 0103 physical sciences, Near-field scanning optical microscope, Spiral (railway), Quantum Physics (quant-ph), 010306 general physics, 0210 nano-technology, Chirality (chemistry), Quantum, Plasmon, Spin-½
Abstract: International audience; We discuss an alternate paradigm: the chiral electromagnetic local density of states (LDOS) in a spiral plasmonic nanostructure. In both classical and quantum regimes, we reveal using near-field scanning optical microscopy (NSOM) in combination with spin analysis that a spiral cavity possesses spin-dependent local optical modes. We expect this work to lead to promising directions for future quantum plasmonic device development, highlighting the potentials of chirality in quantum information processing.
Published: 2016
Full Text: View/download PDF

28. Giant Mesoscopic Fluctuations and Long-Range Superconducting Correlations in Superconductor-Ferromagnet Structures

Author: Alexandre I. Buzdin, A. S. Mel'nikov, Institute for Physics of Microstructures of the RAS, Russian Academy of Sciences [Moscow] (RAS), Lobachevsky State University of Nizhny Novgorod, University of Nizhny Novgorod, Laboratoire Ondes et Matière d'Aquitaine (LOMA), Université de Bordeaux (UB)-Centre National de la Recherche Scientifique (CNRS), and ANR-15-CE24-0008,SUPERTRONICS,Control de courants supraconducteurs via des effets de spin et de champ: fondements pour une électronique non conventionnelle(2015)
Subjects: Physics, Superconductivity, Mesoscopic physics, Local density of states, Condensed matter physics, Condensed Matter - Superconductivity, FOS: Physical sciences, General Physics and Astronomy, 02 engineering and technology, 021001 nanoscience & nanotechnology, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, 01 natural sciences, Superconductivity (cond-mat.supr-con), [PHYS.COND.CM-S]Physics [physics]/Condensed Matter [cond-mat]/Superconductivity [cond-mat.supr-con], Magnetization, Ferromagnetism, Josephson current, Condensed Matter::Superconductivity, 0103 physical sciences, Cooper pair, 010306 general physics, 0210 nano-technology, Wave function
Abstract: The fluctuating superconducting correlations emerging in dirty hybrid structures in conditions of the strong proximity effect are demonstrated to affect the validity range of the widely used formalism of Usadel equations at mesoscopic scales. In superconductor -- ferromagnet (SF) structures these giant mesoscopic fluctuations originating from the interference effects for the Cooper pair wave function in the presence of the exchange field can be responsible for an anomalously slow decay of superconducting correlations in a ferromagnet even when the non-collinear and spin-orbit effects are negligible. The resulting sample-to-sample fluctuations of the Josephson current in SFS junctions and local density of states in SF hybrid structures can provide an explanation of the long range proximity phenomena observed in mesoscopic samples with collinear magnetization., 7 pages, 3 figures
Published: 2016
Full Text: View/download PDF

29. Nanoantenna for Electrical Generation of Surface Plasmon Polaritons

Author: Jean-Jacques Greffet, François Marquier, F. Bigourdan, Jean-Paul Hugonin, Christophe Sauvan, Laboratoire Charles Fabry / Naphel, Laboratoire Charles Fabry (LCF), and Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS)-Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS)
Subjects: Physics, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], Local density of states, business.industry, Surface plasmon, General Physics and Astronomy, Physics::Optics, 02 engineering and technology, 021001 nanoscience & nanotechnology, 7. Clean energy, 01 natural sciences, Surface plasmon polariton, law.invention, 010309 optics, law, 0103 physical sciences, Optoelectronics, Light emission, Emission spectrum, Scanning tunneling microscope, 0210 nano-technology, business, Plasmon, Localized surface plasmon
Abstract: International audience; Light emission by inelastic tunneling has been known for many years. Recently, this technique has been used to generate surface plasmons using a scanning tunneling microscope tip. The emission process suffers from a very low efficiency lower than a photon in 10 4 electrons. We introduce a resonant plasmonic nanoantenna that allows both enhancing the power conversion to surface plasmon polaritons by more than 2 orders of magnitude and narrowing the emission spectrum. The physics of the emission process is analyzed in terms of local density of states and the efficiency of the nanoantenna to radiate surface plasmon polaritons.
Published: 2016
Full Text: View/download PDF

30. Atomic and electronic structure of trilayer graphene/SiC(0001): Evidence of Strong Dependence on Stacking Sequence and charge transfer

Author: Mathieu G. Silly, Matteo Calandra, Thomas Brumme, Fausto Sirotti, Abdelkarim Ouerghi, Jean-Christophe Girard, Antoine Barbier, Francesco Mauri, Debora Pierucci, Centre de Nanosciences et de Nanotechnologies [Marcoussis] (C2N), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Institut de minéralogie, de physique des matériaux et de cosmochimie (IMPMC), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de recherche pour le développement [IRD] : UR206-Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS), Max Planck Institute for the Structure and Dynamics of Matter (MPSD), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Service de physique de l'état condensé (SPEC - UMR3680), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome], Fondazione Istituto Italiano di Tecnologia, Genova, Muséum national d'Histoire naturelle (MNHN)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de recherche pour le développement [IRD] : UR206-Centre National de la Recherche Scientifique (CNRS), and Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome] (UNIROMA)
Subjects: Multidisciplinary, Materials science, Local density of states, Condensed matter physics, Graphene, Stacking, Angle-resolved photoemission spectroscopy, 02 engineering and technology, Electronic structure, Substrate (electronics), 021001 nanoscience & nanotechnology, 01 natural sciences, Article, law.invention, law, 0103 physical sciences, Density functional theory, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], 010306 general physics, 0210 nano-technology, Electronic band structure
Abstract: The transport properties of few-layer graphene are the directly result of a peculiar band structure near the Dirac point. Here, for epitaxial graphene grown on SiC, we determine the effect of charge transfer from the SiC substrate on the local density of states (LDOS) of trilayer graphene using scaning tunneling microscopy/spectroscopy and angle resolved photoemission spectroscopy (ARPES). Different spectra are observed and are attributed to the existence of two stable polytypes of trilayer: Bernal (ABA) and rhomboedreal (ABC) staking. Their electronic properties strongly depend on the charge transfer from the substrate. We show that the LDOS of ABC stacking shows an additional peak located above the Dirac point in comparison with the LDOS of ABA stacking. The observed LDOS features, reflecting the underlying symmetry of the two polytypes, were reproduced by explicit calculations within density functional theory (DFT) including the charge transfer from the substrate. These findings demonstrate the pronounced effect of stacking order and charge transfer on the electronic structure of trilayer or few layer graphene. Our approach represents a significant step toward understand the electronic properties of graphene layer under electrical field.
Published: 2016
Full Text: View/download PDF

31. Statistical theory of designed quantum transport across disordered networks

Author: Mattia Walschaers, Andreas Buchleitner, Thomas Wellens, Roberto Mulet, and University of Freiburg [Freiburg]
Subjects: PACS number(s): 05.60.Gg,03.65.Xp,72.10.−d,82.20.Xr, Gaussian, FOS: Physical sciences, 01 natural sciences, 010305 fluids & plasmas, symbols.namesake, [PHYS.QPHY]Physics [physics]/Quantum Physics [quant-ph], Quantum mechanics, 0103 physical sciences, Computer Simulation, Statistical theory, 010306 general physics, Scaling, Quantum, Eigenvalues and eigenvectors, Probability, Mathematics, Random graph, Quantum Physics, Local density of states, Disordered Systems and Neural Networks (cond-mat.dis-nn), Condensed Matter - Disordered Systems and Neural Networks, Models, Theoretical, Physics - Data Analysis, Statistics and Probability, symbols, Quantum Theory, Quantum Physics (quant-ph), Random matrix, Data Analysis, Statistics and Probability (physics.data-an)
Abstract: We explain how centrosymmetry, together with a dominant doublet in the local density of states, can guarantee interference-assisted, strongly enhanced, strictly coherent quantum excitation transport between two predefined sites of a random network of two-level systems. Starting from a generalisation of the chaos assisted tunnelling mechanism, we formulate a random matrix theoretical framework for the analytical prediction of the transfer time distribution, of lower bounds of the transfer efficiency, and of the scaling behaviour of characteristic statistical properties with the size of the network., 23 pages, 8 figures
Published: 2015
Full Text: View/download PDF

32. Electronic modulations in a single wall carbon nanotube induced by the Au(111) surface reconstruction

Author: Yousoo Kim, Maki Kawai, Sylvain Clair, Hyung-Joon Shin, Institut des Matériaux, de Microélectronique et des Nanosciences de Provence (IM2NP), Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), RIKEN - Institute of Physical and Chemical Research [Japon] (RIKEN), Ulsan National Institute of Science and Technology (UNIST), Department of Advanced Materials Science, Graduate School of Frontier Sciences, The University of Tokyo, The University of Tokyo (UTokyo), and Aix Marseille Université (AMU)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Local density of states, Materials science, Physics and Astronomy (miscellaneous), chemistry.chemical_element, Substrate (electronics), Carbon nanotube, [CHIM.MATE]Chemical Sciences/Material chemistry, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, Molecular physics, law.invention, Condensed Matter::Materials Science, Vacuum deposition, chemistry, law, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Atomic physics, Scanning tunneling microscope, Carbon, Surface reconstruction, ComputingMilieux_MISCELLANEOUS, Surface states
Abstract: The structural and electronic structure of single wall carbon nanotubes adsorbed on Au(111) has been investigated by low-temperature scanning tunneling microscopy and spectroscopy. The nanotubes were dry deposited in situ in ultrahigh vacuum onto a perfectly clean substrate. In some cases, the native herringbone reconstruction of the Au(111) surface interacted directly with adsorbed nanotubes and produced long-range periodic oscillations in their local density of states, corresponding to charge transfer modulations along the tube axis. This effect, however, was observed not systematically for all tubes and only for semiconducting tubes.
Published: 2015
Full Text: View/download PDF

33. Plasmonic Hot Printing in Gold Nanoprisms

Author: Erik Dujardin, Sviatlana Viarbitskaya, Christian Girard, Jadab Sharma, Arnaud Arbouet, Alexandre Teulle, Aurélien Cuche, Centre d'élaboration de matériaux et d'études structurales (CEMES), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Nano-Optique et Nanomatériaux pour l'optique (CEMES-NeO), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Groupe NanoSciences (CEMES-GNS), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie de Toulouse (ICT-FR 2599), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3)
Subjects: thermoplasmonics, Materials science, melting, surface plasmon, 02 engineering and technology, 01 natural sciences, law.invention, Metal, LDOS, Optics, law, colloids, 0103 physical sciences, Irradiation, Electrical and Electronic Engineering, [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, 010306 general physics, Plasmon, Local density of states, business.industry, Surface plasmon, 021001 nanoscience & nanotechnology, Laser, Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials, visual_art, Femtosecond, visual_art.visual_art_medium, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Optoelectronics, 0210 nano-technology, business, Excitation, Biotechnology
Abstract: cited By 18; International audience; The raster-scanned irradiation of ultrathin sub-micrometer crystalline gold colloidal prisms with the tightly focused spot of a femtosecond, near-infrared laser triggers the deterministic deformation and partial melting of nanometer-sized areas of the nanoprisms. The morphological modification of the Au nanoprisms evidences extremely localized sources of heat, the in-plane distribution of which varies with the particle shape and laser polarization. We demonstrate for the first time the direct relationship between heat source density and surface plasmon local density of states (SP-LDOS), which describes quantitatively the rich modal structure of the surface plasmons sustained by the 2D metallic platelets, independently of the knowledge of the illumination configuration. Green’s Dyadic numerical simulations confirm that the optical excitation of the 2D SP modes results in the subwavelength hot imprinting of the SP modal pattern onto the metal surface.
Published: 2015
Full Text: View/download PDF

34. Modal engineering of Surface Plasmons in apertured Au Nanoprisms

Author: Sviatlana Viarbitskaya, Aurélien Cuche, Jadab Sharma, Arnaud Arbouet, Erik Dujardin, Christian Girard, Nano-Optique et Nanomatériaux pour l'optique (CEMES-NeO), Centre d'élaboration de matériaux et d'études structurales (CEMES), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie de Toulouse (ICT-FR 2599), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA), Université de Bourgogne (UB), Groupe NanoSciences (CEMES-GNS), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), and Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [PHYS]Physics [physics], Multidisciplinary, Materials science, Local density of states, business.industry, Linear polarization, Surface plasmon, Physics::Optics, Optical field, Focused ion beam, Article, Femtosecond, Optoelectronics, business, Plasmon, Localized surface plasmon
Abstract: Crystalline gold nanoprisms of sub-micrometric size sustain high order plasmon modes in the visible and near infrared range that open a new realm for plasmon modal design, integrated coplanar devices and logic gates. In this article, we explore the tailoring of the surface plasmon local density of states (SP-LDOS) by embedding a single defect, namely a small hole, carved in the platelet by focused ion beam (FIB). The change in the SP-LDOS of the hybrid structure is monitored by two-photon luminescence (TPL) microscopy. The dependency of the two-dimensional optical field intensity maps on the linear polarization of the tightly focused femtosecond laser beam reveals the conditions for which the hole defect significantly affects the initial modes. A detailed numerical analysis of the spectral characteristics of the SP-LDOS based on the Green dyadic method clearly indicates that the hole size and location can be exploited to tune or remove selected SP modes.
Published: 2015
Full Text: View/download PDF

35. Tunneling spectroscopy of Majorana-Kondo devices

Author: Reinhold Egger, Erik Eriksson, Christophe Mora, Andrea Nava, Laboratoire Pierre Aigrain (LPA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Fédération de recherche du Département de physique de l'Ecole Normale Supérieure - ENS Paris (FRDPENS), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut für Theoretische Physik, Heinrich Heine Universität Düsseldorf = Heinrich Heine University [Düsseldorf], Fédération de recherche du Département de physique de l'Ecole Normale Supérieure - ENS Paris (FRDPENS), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)
Subjects: CONTACT, Nanowire, FOS: Physical sciences, 02 engineering and technology, Electron, 01 natural sciences, Condensed Matter - Strongly Correlated Electrons, Quantum mechanics, Condensed Matter::Superconductivity, 0103 physical sciences, Bound state, Mesoscale and Nanoscale Physics (cond-mat.mes-hall), SUPERCONDUCTOR, 010306 general physics, Quantum tunnelling, [PHYS.COND.CM-MSQHE]Physics [physics]/Condensed Matter [cond-mat]/Mesoscopic Systems and Quantum Hall Effect [cond-mat.mes-hall], NANOWIRE, LUTTINGER LIQUID, FERMIONS, SIGNATURE, Physics, Superconductivity, Mesoscopic physics, Local density of states, Condensed matter physics, Strongly Correlated Electrons (cond-mat.str-el), Condensed Matter - Mesoscale and Nanoscale Physics, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, Electronic, Optical and Magnetic Materials, MAJORANA, Condensed Matter::Strongly Correlated Electrons, 0210 nano-technology
Abstract: We study the local density of states (LDOS) in systems of Luttinger-liquid nanowires connected to a common mesoscopic superconducting island, in which Majorana bound states give rise to different types of topological Kondo effects. We show that electron interactions enhance the low-energy LDOS in the leads close to the island, with unusual exponents due to Kondo physics that can be probed in tunneling experiments., 9 pages, 2 figures
Published: 2014
Full Text: View/download PDF

36. Scanning Probe Electronic Imaging of Lithographically Patterned Quantum Rings

Author: Vincent Bayot, Benoît Hackens, Serge Huant, Hermann Sellier, Frederico Rodrigues Martins, Marco G. Pala, Institut de la matière condensée et des nanosciences / Institute of Condensed Matter and Nanosciences (IMCN), Université Catholique de Louvain = Catholic University of Louvain (UCL), Nano-Electronique Quantique et Spectroscopie (QuNES), Institut Néel (NEEL), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS), Institut de Microélectronique, Electromagnétisme et Photonique - Laboratoire d'Hyperfréquences et Caractérisation (IMEP-LAHC), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS), Nano-Optique et Forces (NOF), Ed. by V. Fomin, and ANR-07-NANO-0049,MICATEC,MICroscopie Avancée du Transport Electronique Cohérent(2007)
Subjects: Physics, Mesoscopic physics, Local density of states, Condensed matter physics, Coulomb Blockade, Coulomb blockade, Scanning gate microscopy, 02 engineering and technology, Quantum Ring, Quantum imaging, Quantum Hall effect, 021001 nanoscience & nanotechnology, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, Atomic Force Microscopy Cantilever, Electron Probability Density, 01 natural sciences, Magnetic field, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], 0103 physical sciences, Conductance Image, 010306 general physics, 0210 nano-technology, Quantum
Abstract: International audience; Quantum rings patterned from two-dimensional semiconductor heterostructures exhibit a wealth of quantum transport phenomena at low temperature and in a magnetic field that can be mapped in real space thanks to dedicated scanning probe techniques. Here, we summarize our studies of GaInAs-based quantum rings by means of scanning gate microscopy both at low magnetic field, where Aharonov-Bohm interferences and the electronic local density of states are imaged, and at high magnetic field and very low temperatures, where the scanning probe can image Coulomb islands in the quantum Hall regime. This allows decrypting the apparent complexity of the magneto-resistance of a mesoscopic system in this regime. Beyond imaging and beyond a strict annular shape of the nanostructure, we show that this scanning-probe technique can also be used to unravel a new counter-intuitive behavior of branched-out rectangular quantum rings, which turns out to be a mesoscopic analog of the Braess paradox, previously known for road or other classical networks only.
Published: 2014
Full Text: View/download PDF

37. Electronic surface potential from angle-resolved photoemission

Author: Yannick Fagot-Révurat, Muriel Sicot, Daniel Malterre, Bertrand Kierren, Guillaume Vasseur, Institut Jean Lamour (IJL), and Institut de Chimie du CNRS (INC)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Local density of states, Materials science, Photoemission spectroscopy, Band gap, Inverse photoemission spectroscopy, Scanning tunneling spectroscopy, Angle-resolved photoemission spectroscopy, 02 engineering and technology, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, Electronic, Optical and Magnetic Materials, 0103 physical sciences, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Atomic physics, 010306 general physics, 0210 nano-technology, Electronic band structure, Surface states
Abstract: Équipe 102 : Surfaces et Spectroscopies; International audience; We present a methodology to determine the periodic potential of a surface from angle-resolved photoemission spectroscopy. By mapping the band structure and measuring the energy gap widths at high symmetry points of the surface Brillouin zone, the first Fourier components of the potential can be estimated. This method has been applied in the case of the reconstructed Ag/Cu(111) surface where controlled potassium atom doping has been used to precisely tune the band gap energies. This potential determination allows one to calculate the local density of states which is found to be in very good agreement with scanning tunneling spectroscopy data.
Published: 2014
Full Text: View/download PDF

38. Nonlinear electric transport in graphene with magnetic disorder

Author: Alberto Verga, Arnaud Demion, Institut des Matériaux, de Microélectronique et des Nanosciences de Provence (IM2NP), Aix Marseille Université (AMU)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS), Centre de Physique Théorique - UMR 7332 (CPT), and Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)
Subjects: Local density of states, Materials science, Condensed Matter - Mesoscale and Nanoscale Physics, Condensed matter physics, Graphene, FOS: Physical sciences, 02 engineering and technology, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, Electronic, Optical and Magnetic Materials, law.invention, Paramagnetism, Magnetization, T-symmetry, law, Phase (matter), Electric field, Mesoscale and Nanoscale Physics (cond-mat.mes-hall), 0103 physical sciences, Antiferromagnetism, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], 010306 general physics, 0210 nano-technology
Abstract: The influence of magnetic impurities on the transport properties of graphene is investigated in the regime of strong applied electric fields. As a result of electron-hole pair creation, the response becomes nonlinear and dependent on the magnetic polarization. In the paramagnetic phase, time reversal symmetry is statistically preserved, and transport properties are similar to the clean case. At variance, in the antiferromagnetic phase, the system undergoes a transition between a superdiffusive to a subdiffusive spreading of a wave packet, signaling the development of localized states. This critical regime is characterized by the appearance of electronic states with a multifractal geometry near the gap. The local density of states concentrates in large patches having a definite charge-spin correlation. In this state, the conductivity tends to half the minimum conductivity of clean graphene., 9 pages, 8 figures
Published: 2014
Full Text: View/download PDF

39. Emission, scattering and localization of light in complex structures: From nanoantennas to disordered media

Author: Cazé, Alexandre, Institut Langevin - Ondes et Images (UMR7587) (IL), Sorbonne Université (SU)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Paris (UP)-Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris VI, and Rémi Carminati(remi.carminati@espci.fr)
Subjects: Strong coupling, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], Corrélations de speckle, Nanooptique, Nanooptics, Cross Density Of States, Local Density Of States, Densité locale d'états électromagnétiques, Films métalliques désordonnés, Weak coupling, Speckle correlations, Localisation d'Anderson, Disordered metallic films, Anderson localization, Couplage fort
Abstract: Using nanostructures to confine light allows to increase the interaction between an emitter and electromagnetic radiation. In this thesis, we use a classical formalism (presented in Chap. 1) to describe this interaction in various contexts, that can be gathered in two parts (respectively Parts II and III). First, we study the apparition of localized modes in the near field of complex metallic structures. We study numerically the spatial distribution of the local density of states (LDOS) in the vicinity of two different structures: gold nanoantennas and disordered metallic films. Our results allow us to discriminate between radiative and non-radiative modes. We introduce the concept of cross density of states (CDOS) to quantitatively study the intrinsic spatial coherence associated with the modal structure of a complex medium. We use the CDOS to demonstrate an overall spatial squeezing of the modes near the electric percolation of disordered metallic films. Then, we focus on strongly scattering media. By illuminating such structures by a coherent source, one obtains a chaotic intensity pattern called speckle. First, we use a diagramatic method to demonstrate an anticorrelation between the reflected and transmitted speckle patterns in the case of a diffusive slab in the mesoscopic regime. Then, we study the C0 correlation, that appears the source is embedded inside the medium. We propose a general derivation of the equality between the C0 correlation and the normalized fluctuations of the LDOS, and emphasize the fundamental role of near-field interactions. Finally, we study two-dimensional disordered media in the Anderson localized regime. We observe the strong coupling regime between such a mode and a resonant scatterer, in excellent agreement with theoretical predictions.; Utiliser des milieux nanostructurés pour confiner la lumière permet d'augmenter l'interaction entre un émetteur et le rayonnement électromagnétique. Dans cette thèse, nous utilisons un formalisme classique (présenté au Chap. 1) pour décrire cette interaction dans différents contextes, qui peuvent être regroupés en deux parties (respectivement Parties II et III). Dans un premier temps, nous étudions l'apparition de modes localisés en champ proche de structures complexes. Nous nous intéressons à deux différents types de structures: des nanoantennes d'or et des films d'or désordonnés. Nos résultats nous permettent de discerner les modes radiatifs et non-radiatifs. Nous introduisons le concept de Cross Density Of States (CDOS) pour décrire quantitativement la cohérence spatiale intrinsèque associée à la structure modale d'un milieu complexe. Nous démontrons ainsi une réduction de l'extention spatiale des modes au voisinage de la percolation électrique des films d'or désordonnés. Nous nous intéressons ensuite à des milieux fortement diffusants. En éclairant de telles structures par une source cohérente, on obtient une figure d'intensité complexe appelée speckle. Nous utilisons une méthode diagrammatique pour démontrer une corrélation négative entre les figures de speckle réfléchie et transmise à travers une tranche dans le régime mésoscopique. Nous nous intéressons ensuite à la corrélation C0, qui apparait lorsque la source est enfouie dans le milieu. Nous proposons une démonstration générale de l'égalité entre la corrélation C0 et les fluctuations normalisées de la LDOS, et soulignons le rôle fondamental des interactions de champ proche. Finalement, nous observons numériquement le régime de couplage fort entre un diffuseur résonnant et un mode localisé d'Anderson au sein d'un milieu désordonné 2D.
Published: 2013

40. FAÇONNAGE DE MODES PLASMONS DANS DES COLLOÏDES D’OR

Author: TEULLE, Alexandre, Centre d'élaboration de matériaux et d'études structurales (CEMES), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Université Toulouse 3 Paul Sabatier (UT3 Paul Sabatier), Erik DUJARDIN, Christian GIRARD, Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie de Toulouse (ICT-FR 2599), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)
Subjects: [PHYS]Physics [physics], [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], electron energy loss spectroscopy, local density of states, two photon luminescence, or, gold, plasmonique, méthode de Green dyadique, spectroscopie de pertes d’énergie, plasmonics, photomigration, luminescence à deux photons, Green dyadic method, colloids, simulations, densité locale d’états, colloïdes
Abstract: The main objective of this thesis is to interpret experimental measurements of the plasmonic properties of goldcolloidal particles.First, we study the optical near-field distribution around nano-platelets thanks to the photomigration technique. Thisindirect photo-chemical mapping uncovers a size effect by shining at 457 nm and 514 nm particles of different sizes, suggesting a quasi-modal response from the surface plasmons supported by these structures. This peculiar response is evidenced in the case of colloidal triangles of 500 nm side length.Then, we show that Two Photon Luminescence (TPL) offers another original way to probe the electromagnetic fielddistribution inside Au particles. We focus the TPL study on gold nano-rods and platelets. TPL maps show a strong confinement of the electromagnetic field inside these objects. Signal localization can be controlled by adjusting incident polarization.Simultaneously, we have developed a new tool based on the Green Dyadic Method (GDM) to reproduce and analyze TPL maps. They confirm specific near-field localization in the metal and provide a new insight into wavelength and particle shape influence. Our model suggests that TPL gives also access to the local density of plasmonic states in the particle and consequently that the coupling between two gold platelets could lead to a new design of a plasmonic modal logic gate. Finally, we have investigated the optical properties of gold nanoparticle chains. These nanoparticles fuse under theelectron beam of the TEM. The fusion shifts plasmons resonances of the chains towards the infrared region. These plasmonic modes have been studied spatially and spectrally using Electron Energy Loss Spectroscopy (EELS). We have developed a theoretical model showing the link between the energy loss of a swift electron and the local density of states. Using the GDM, we have computed EELS maps of these nanoparticle chains.; Cette thèse a pour objectif principal d’interpréter des mesures expérimentales des propriétés plasmoniques denanoparticules d’or cristallines de différentes morphologies.Nous étudions tout d’abord, grâce à un film photosensible, la distribution du champ local autour de nano-prismes d’or.Cette cartographie indirecte révèle un effet de taille en irradiant à 457 nm et 514nm des objets de formes identiques mais de dimensions différentes, suggérant une réponse quasi-modale des plasmons supportés par ces structures. Cette réponse quasimodale est mise en évidence dans le cas de prismes triangulaires de 500 nm de côté.Dans une seconde étape, nous montrons que la luminescence à deux photons (TPL) offre un autre moyen original desonder la distribution du champ électromagnétique à l’intérieur de ces particules. En particulier, nous considérons le cas des nano-bâtonnets et des prismes d’or. Les cartes TPL montrent un fort confinement du champ à l’intérieur de ces objets. La localisation du signal peut être contrôlée en ajustant la polarisation incidente. Parallèlement, nous avons développé un nouvel outil de simulation pour reproduire et interpréter les cartes TPL. Elles confirment la spatialisation spécifique du champ proche et nous renseignent sur l’influence de la longueur d’onde et de la forme des prismes. Notre modèle suggère que la TPL donne aussi accès à la densité locale d’états plasmoniques dans la particule, et que le couplage entre deux nano-prismes peut constituer une nouvelle façon de concevoir des portes logiques modales plasmoniques.Enfin, nous avons étudié les propriétés optiques de chaines de sphères d’or d’une dizaine de nanomètres de diamètre. Les particules constituant ces chaines fusionnent sous l’effet du faisceau du microscope électronique en transmission ce qui conduit à un décalage dans l’infrarouge des modes de résonance plasmon. Nous avons caractérisé spatialement et spectralement ces modes plasmons par spectroscopie de pertes d’énergie (EELS). Grâce à la polyvalence du formalisme des fonctions de Green, et en nous appuyant sur une modélisation théorique montrant le lien entre signal de perte et densité locale d’états, nous avons simulé des cartes EELS de ces objets.
Published: 2013

41. On the theory of the proximity effect in atomic scale superconducting/normal metal multilayered structures

Author: Xavier Montiel, Alexandre I. Buzdin, International Institute of Physics [Natal], Universidade Federal do Rio Grande do Norte [Natal] (UFRN), Laboratoire Ondes et Matière d'Aquitaine (LOMA), Université de Bordeaux (UB)-Centre National de la Recherche Scientifique (CNRS), Institut Universitaire de France (IUF), Ministère de l'Education nationale, de l’Enseignement supérieur et de la Recherche (M.E.N.E.S.R.), ANR Program 'MASH' and the LabEX 'Amadeus' Program, ANR-12-BS04-0016,MASH,Etats de Majorana et d'Andreev dans des circuits hybrides combinant des matériaux magnétiques et supraconducteurs(2012), and ANR-10-IDEX-0003,IDEX BORDEAUX,Initiative d'excellence de l'Université de Bordeaux(2010)
Subjects: Coupling, Superconductivity, Materials science, Local density of states, Nanostructure, Condensed matter physics, Metals and Alloys, 02 engineering and technology, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, Atomic units, Spectral line, [PHYS.COND.CM-S]Physics [physics]/Condensed Matter [cond-mat]/Superconductivity [cond-mat.supr-con], Condensed Matter::Superconductivity, 0103 physical sciences, Materials Chemistry, Ceramics and Composites, Proximity effect (superconductivity), Electrical and Electronic Engineering, 010306 general physics, 0210 nano-technology, Electronic band structure
Abstract: International audience; We determine the influence of the electronic band structure and interlayer coupling on the superconducting properties of quasi-two-dimensional superconductor (S)-normal metal (N) nanostructures. An exact analytical solution of the Gor'kov equations which describes the superconducting properties and the local density of states in S/N/.../N multilayers is found. We study the influence of the electronic spectra, the interlayer coupling and the total number of layers on the local density of states and the superconducting properties of S/N/.../N structures. Moreover, we investigate the impact of the parameters mentioned above on the critical Josephson current in S/N/.../N/S junctions.
Published: 2013
Full Text: View/download PDF

42. Theory of the spontaneous optical emission of nanosize photonic and plasmon resonators

Author: Philippe Lalanne, Ivan S. Maksymov, Jean-Paul Hugonin, Christophe Sauvan, lp2n-03,lp2n-13, Laboratoire Photonique, Numérique et Nanosciences (LP2N), Université Sciences et Technologies - Bordeaux 1-Institut d'Optique Graduate School (IOGS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut d'Optique Graduate School (IOGS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Charles Fabry / Naphel, Laboratoire Charles Fabry (LCF), and Université Paris-Sud - Paris 11 (UP11)-Institut d'Optique Graduate School (IOGS)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11)-Institut d'Optique Graduate School (IOGS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], Local density of states, business.industry, Nanophotonics, General Physics and Astronomy, Physics::Optics, 02 engineering and technology, Dissipation, 021001 nanoscience & nanotechnology, 01 natural sciences, Dipole, Resonator, Quantum mechanics, 0103 physical sciences, Dissipative system, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, Photonics, 010306 general physics, 0210 nano-technology, business, Plasmon
Abstract: International audience; We provide a self-consistent electromagnetic theory of the coupling between dipole emitters and dissipative nanoresonators. The theory that relies on the concept of quasinormal modes with complex frequencies provides an accurate closed-form expression for the electromagnetic local density of states of any photonic or plasmonic resonator with strong radiation leakage, absorption, and material dispersion. It represents a powerful tool to calculate and conceptualize the electromagnetic response of systems that are governed by a small number of resonance modes.We use the formalism to revisit Purcell's factor. The new formula substantially differs from the usual one; in particular, it predicts that a spectral detuning between the emitter and the resonance does not necessarily result in a Lorentzian response in the presence of dissipation. Comparisons with fully vectorial numerical calculations for plasmonic nanoresonators made of gold nanorods evidence the high accuracy of the predictions achieved by our semianalytical treatment.
Published: 2013
Full Text: View/download PDF

43. Electronic and magnetic structure of the Cr$(001)$ surface

Author: P Habibi, Alexander Smogunov, Cyrille Barreteau, Service de Physique et de Chimie des Surfaces et Interfaces (SPCSI), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)
Subjects: Local density of states, Condensed matter physics, Magnetic moment, Chemistry, Fermi level, Scanning tunneling spectroscopy, 02 engineering and technology, Surface phonon, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, symbols.namesake, 0103 physical sciences, symbols, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], General Materials Science, Density functional theory, Surface layer, 010306 general physics, 0210 nano-technology, Surface states
Abstract: International audience; Combined Density Functional Theory (DFT) and Tight-Binding (TB) calculations are carried out to study the electronic and magnetic structure of the $(001)$ surface of Chromium. Our aim is to identify and characterize the most prominent electronic surface states and make the connection with the main experimental results. We show that a low dispersive minority spin surface state at the center of the Surface Brillouin zone plays a crucial role. This surface states of $\Delta_1$ symmetry at 0.58eV above the Fermi level exhibits predominantly a $d_{z^2}$ as well as $p_z$ orbital character. Local density of states (LDOS) analysis in the vacuum above the surface shows that the sharp feature originating from this surface state persists far away above the surface because of the slow decay rate of $p_z$ wave functions. Finally by artificially lowering the surface magnetic moment $m_S$ on the outermost surface layer we find an excellent agreement with experiments for $m_S=1.75\mu_B$. In addition we propose that some extra Spin Polarized Scanning Tunneling Spectroscopy (SP-STS) experiments should be made at smaller tip-surface distances to reveal additional features originating from majority spin $d_{z^2}$ surface states.
Published: 2013
Full Text: View/download PDF

44. Tuning the electromagnetic local density of states in graphene-covered systems via strong coupling with graphene plasmons

Author: Philippe Ben-Abdallah, Yannick De Wilde, Yvon Cordier, François Marquier, Jean-Paul Hugonin, Jean-Jacques Greffet, Ali Belarouci, Luc G. Fréchette, Riccardo Messina, Laboratoire Charles Fabry / Naphel, Laboratoire Charles Fabry (LCF), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS)-Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS), Institut Langevin - Ondes et Images (UMR7587) (IL), Sorbonne Université (SU)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Paris (UP)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Nanotechnologies Nanosystèmes (LN2 ), Université de Sherbrooke (UdeS)-École Centrale de Lyon (ECL), Université de Lyon-Université de Lyon-École supérieure de Chimie Physique Electronique de Lyon (CPE)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Centre de Recherche sur l'Hétéro-Epitaxie et ses Applications, Centre National de la Recherche Scientifique (CNRS), Université Paris-Sud - Paris 11 (UP11)-Institut d'Optique Graduate School (IOGS)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11)-Institut d'Optique Graduate School (IOGS)-Centre National de la Recherche Scientifique (CNRS), Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Nanotechnologies et Nanosystèmes [Sherbrooke] (LN2), Université Joseph Fourier - Grenoble 1 (UJF)-Université de Sherbrooke (UdeS)-École Centrale de Lyon (ECL), Université de Lyon-Université de Lyon-École Supérieure de Chimie Physique Électronique de Lyon (CPE)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), and Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Electromagnetic field, Materials science, FOS: Physical sciences, Physics::Optics, 02 engineering and technology, 01 natural sciences, law.invention, law, Mesoscale and Nanoscale Physics (cond-mat.mes-hall), 0103 physical sciences, Polariton, Physics::Atomic and Molecular Clusters, [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, 010306 general physics, Plasmon, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], Local density of states, Condensed Matter - Mesoscale and Nanoscale Physics, Condensed matter physics, Graphene, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 3. Good health, Electronic, Optical and Magnetic Materials, Surface wave, Thermal radiation, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], Quasiparticle, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, 0210 nano-technology, Optics (physics.optics), Physics - Optics
Abstract: It is known that the near-field spectrum of the local density of states of the electromagnetic field above a SiC/air interface displays an intense narrow peak due to the presence of a surface polariton. It has been recently shown that this surface wave can be strongly coupled with the sheet plasmon of graphene in graphene-SiC heterosystems. Here, we explore the interplay between these two phenomena and demonstrate that the spectrum of the electromagnetic local density of states in these systems presents two peaks whose position depends dramatically both on the distance to the interface and on the chemical potential of graphene. This paves the way towards the active control of the local density of states., 6 pages, 4 figures
Published: 2013
Full Text: View/download PDF

45. Blackbody spectrum revisited in the near field

Author: Arthur Babuty, Yannick De Wilde, Pierre-Olivier Chapuis, Karl Joulain, Jean-Jacques Greffet, Institut Langevin - Ondes et Images (UMR7587) (IL), Sorbonne Université (SU)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Paris (UP)-Centre National de la Recherche Scientifique (CNRS), Institut Pprime (PPRIME), Université de Poitiers-ENSMA-Centre National de la Recherche Scientifique (CNRS), Centre de Thermique de Lyon (CETHIL), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Charles Fabry / Naphel, Laboratoire Charles Fabry (LCF), and Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS)-Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS)
Subjects: [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], Materials science, Local density of states, business.industry, Physics::Instrumentation and Detectors, General Physics and Astronomy, Infrared spectroscopy, Near and far field, 02 engineering and technology, 021001 nanoscience & nanotechnology, 01 natural sciences, Spectral line, Optics, Thermal radiation, Excited state, 0103 physical sciences, Black-body radiation, Atomic physics, 010306 general physics, 0210 nano-technology, Spectroscopy, business
Abstract: International audience; We report local spectra of the near-field thermal emission recorded by a Fourier transform infrared spectrometer, using a tungsten tip as a local scatterer coupling the near-field thermal emission to the far field. Spectra recorded on silicon carbide and silicon dioxide exhibit temporal coherence due to thermally excited surface waves. Finally, we evaluate the ability of this spectroscopy to probe the frequency dependence of the electromagnetic local density of states.
Published: 2013
Full Text: View/download PDF

46. Structure and stability of the interface between graphene and 6H-SiC(000-1) (3x3) : an STM and ab-initio study

Author: Fanny Hiebel, Laurence Magaud, Pierre Mallet, Jean-Yves Veuillen, Systèmes hybrides de basse dimensionnalité (HYBRID), Institut Néel (NEEL), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS), Nano-Electronique Quantique et Spectroscopie (QuNES), and Nanoscience Foundation, RTRA project 'DispoGraph' Cible 07 and Cible 08 Région Rhône-Alpes
Subjects: Materials science, ab-initio calculations, Acoustics and Ultrasonics, Ab initio, Nanotechnology, 02 engineering and technology, Electronic structure, SiC C face, 01 natural sciences, law.invention, symbols.namesake, law, Ab initio quantum chemistry methods, 0103 physical sciences, 010306 general physics, Quantum tunnelling, Local density of states, Condensed matter physics, Graphene, Fermi level, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, 73.20.At, 73.22.Pr, 68.65.Pq, Scanning Tunneling Microscopy, symbols, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Scanning tunneling microscope, 0210 nano-technology
Abstract: We examine in detail the structure and evolution upon annealing of the SiC(3 × 3) reconstruction which is known to be present at the interface between the SiC–C face substrate and the graphene layer for samples prepared in high vacuum. We use ab initio calculations to test the validity of proposed or classical structural models in comparison with scanning tunnelling microscopy (STM) images. We analyse the electronic structure of the bare surface and detect interface states which can pin the surface Fermi level. From a comparison of the signal coming from the bare and graphene-covered SiC(3 × 3) reconstruction we propose that the transparency of the graphene in high-bias STM images results from an enhancement of the local density of states of the interface plane by the graphene layer. We discuss the thermal stability of the SiC(3 × 3) surface, and show that it transforms more easily into the SiC(2 × 2)C reconstruction in the graphene-covered region than for the bare surface. This evolution generates both structural and electronic heterogeneities at the interface.
Published: 2012
Full Text: View/download PDF

47. Large organic molecule chemisorption on the SiC(0001) surface

Author: O. Boudrioua, Philippe Sonnet, Louise Stauffer, Eric Duverger, Haomiao Yang, Young Kuk, Gérald Dujardin, Geneviève Comtet, Samuthira Nagarajan, Andrew J. Mayne, André Gourdon, Institut de Science des Matériaux de Mulhouse (IS2M), Centre National de la Recherche Scientifique (CNRS)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Institut des Sciences Moléculaires d'Orsay (ISMO), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Department of Physics and Astronomy [Seoul], Seoul National University [Seoul] (SNU), Groupe NanoSciences (CEMES-GNS), Centre d'élaboration de matériaux et d'études structurales (CEMES), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie de Toulouse (ICT-FR 2599), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA), Franche-Comté Électronique Mécanique, Thermique et Optique - Sciences et Technologies (UMR 6174) (FEMTO-ST), Université de Technologie de Belfort-Montbeliard (UTBM)-Ecole Nationale Supérieure de Mécanique et des Microtechniques (ENSMM)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre National de la Recherche Scientifique (CNRS), Femto-st, MN2S, Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées (INSA)-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Université de Technologie de Belfort-Montbeliard (UTBM)-Ecole Nationale Supérieure de Mécanique et des Microtechniques (ENSMM)-Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut de Chimie de Toulouse (ICT), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), and Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Materials science, [SPI.NANO] Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, Nanotechnology, 02 engineering and technology, [SPI.MAT] Engineering Sciences [physics]/Materials, 010402 general chemistry, 01 natural sciences, law.invention, [SPI.MAT]Engineering Sciences [physics]/Materials, chemistry.chemical_compound, Adsorption, law, Molecule, [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, [SPI.ACOU]Engineering Sciences [physics]/Acoustics [physics.class-ph], [SPI.ACOU] Engineering Sciences [physics]/Acoustics [physics.class-ph], Local density of states, Image (category theory), 021001 nanoscience & nanotechnology, Condensed Matter Physics, 0104 chemical sciences, Electronic, Optical and Magnetic Materials, Crystallography, chemistry, Chemisorption, Phthalocyanine, Density of states, Scanning tunneling microscope, 0210 nano-technology
Abstract: We present a density-functional theory (DFT) study combined with scanning tunneling microscopy (STM) experiments of the chemisorption of the $N$,$N$\ensuremath{'}-bis(1-hexylheptyl)perylene-3,4:9,10-bis(dicarboximide) molecule, noted here as DHH-PTCDI, on the SiC(0001)-3 \ifmmode\times\else\texttimes\fi{} 3 surface. Five possible adsorption configurations have been investigated in which molecular adsorption occurs on two adjacent Si adatoms via different pairs of atoms of the molecule. We have calculated the energies, structures, density of states, local density of states, and a calculated STM image and show that chemisorption via two oxygen atoms located on the same side of the molecule on two adjacent Si adatoms is the most favorable, in agreement with the experimental STM images. A comparison between the PTCDI and the adsorption of another large organic molecule (phthalocyanine) on the SiC(0001) surface completes this work.
Published: 2012
Full Text: View/download PDF

48. Tight binding within the fourth moment approximation: Efficient implementation and application to liquid Ni droplet diffusion on graphene

Author: J. H. Los, Christophe Bichara, Roland J.-M. Pellenq, Centre Interdisciplinaire de Nanoscience de Marseille (CINaM), and Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, Local density of states, Scale (ratio), Condensed matter physics, Graphene, Second moment of area, 02 engineering and technology, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, Electronic, Optical and Magnetic Materials, law.invention, Tight binding, Fourth moment, Logical conjunction, law, 0103 physical sciences, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Statistical physics, Diffusion (business), 010306 general physics, 0210 nano-technology
Abstract: Application of the fourth moment approximation (FMA) to the local density of states within a tight binding description to build a reactive, interatomic interaction potential for use in large scale molecular simulations, is a logical and significant step forward to improve the second moment approximation, standing at the basis of several, widely used (semi-) empirical interatomic interaction models. In this paper we present a sufficiently detailed description of the FMA and its technical implications, containing the essential elements for an efficient implementation in a simulation code. Using a recent, existing FMA-based model for C-Ni systems, we investigated the size dependence of the diffusion of a liquid Ni cluster on a graphene sheet and find a power law dependence of the diffusion constant on the cluster size (number of cluster atoms) with an exponent very close to -2/3, equal to a previously found exponent for the relatively fast diffusion of solid clusters on a substrate with incommensurate lattice matching. The cluster diffusion exponent gives rise to a specific contribution to the cluster growth law, which is due to cluster coalescence. This is confirmed by a simulation for Ni cluster growth on graphene, which shows that cluster coalescence dominates the initial stage of growth, overruling Oswald ripening.
Published: 2011
Full Text: View/download PDF

49. Electronic properties of Fe clusters on a Au(111) surface

Author: V. Repain, Madhura Marathe, Cyril Chacon, Jérôme Lagoute, S. Rousset, Shobhana Narasimhan, Alexandre Delga, Yann Girard, Laboratoire Matériaux et Phénomènes Quantiques (MPQ (UMR_7162)), Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Theoretical Sciences Unit, and Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR)
Subjects: [PHYS]Physics [physics], Local density of states, Materials science, Nanostructure, 02 engineering and technology, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, Molecular physics, Electronic, Optical and Magnetic Materials, law.invention, Condensed Matter::Materials Science, Effective mass (solid-state physics), Ab initio quantum chemistry methods, law, 0103 physical sciences, Scanning tunneling microscope, 010306 general physics, 0210 nano-technology, Spectroscopy, Electronic properties, Surface states
Abstract: The electronic states of self-organized Fe nanoislands on a Au(111) surface have been investigated using low-temperature scanning tunneling microscopy and spectroscopy. We show that the local density of states is dominated by Shockley surface states confined in the nanostructures. Comparing the experimental dispersion diagram with a free-electron model we derive the effective mass ${m}^{*}=0.39\phantom{\rule{0.16em}{0ex}}{m}_{e}$ and the band onset ${E}_{0}=\ensuremath{-}420$ meV of these states. Ab initio calculations show the existence of the Shockley surface states in the Fe layer, in agreement with the experiment, and reveal that they are fully spin polarized.
Published: 2011

50. A blackbody is not a blackbox

Author: Matteo Smerlak, Centre de Physique Théorique - UMR 6207 (CPT), Centre National de la Recherche Scientifique (CNRS)-Université de Toulon (UTLN)-Université de Provence - Aix-Marseille 1-Université de la Méditerranée - Aix-Marseille 2, Centre de Physique Théorique - UMR 7332 (CPT), Aix Marseille Université (AMU)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS), and Université de la Méditerranée - Aix-Marseille 2-Université de Provence - Aix-Marseille 1-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [PHYS.PHYS.PHYS-CLASS-PH]Physics [physics]/Physics [physics]/Classical Physics [physics.class-ph], Field (physics), General Physics and Astronomy, FOS: Physical sciences, Physics - Classical Physics, 01 natural sciences, 010305 fluids & plasmas, [PHYS.PHYS.PHYS-ED-PH]Physics [physics]/Physics [physics]/Physics Education [physics.ed-ph], symbols.namesake, Theoretical physics, Physics - General Physics, Physics Education (physics.ed-ph), 0103 physical sciences, Radiative transfer, Black-body radiation, Limit (mathematics), Planck, 010306 general physics, Physics, Local density of states, Spectrum (functional analysis), Physics - Physics Education, Classical Physics (physics.class-ph), Resolvent formalism, [PHYS.PHYS.PHYS-GEN-PH]Physics [physics]/Physics [physics]/General Physics [physics.gen-ph], General Physics (physics.gen-ph), symbols
Abstract: We discuss carefully the blackbody approximation, stressing what it is (a limit case of radiative transfer), and what it is not (the assumption that the body is perfectly absorbing, i.e. black). Furthermore, we derive the Planck spectrum without enclosing the field in a box, as is done in most textbooks. Athough convenient, this trick conceals the nature of the idealization expressed in the concept of a blackbody: first, the most obvious examples of approximate blackbodies, stars, are definitely not enclosed in boxes; second, the Planck spectrum is continuous, while the stationary modes of radiation in a box are discrete. Our derivation, although technically less elementary, is conceptually more consistent, and brings the opportunity to introduce to students the important concept of local density of states, via the resolvent formalism., Comment: 6 pages
Published: 2011
Full Text: View/download PDF

Catalog

Books, media, physical & digital resources

See catalog results

Searchworks

Select search scope, currently: Articles Catalog books, media & more in Jio Institute collections Articles journal articles & other e-resources

Search

Search Constraints

Refine your results

Search Limiters

Topic

Publication Year Range

Language

Database

72 results on '"Local density of states"'

Search Results

Catalog

Select search scope, currently: Articles

Catalog

books, media & more in Jio Institute collections

Articles

journal articles & other e-resources