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45 results on '"Christelle Brimont"'

1. Complexity of the dipolar exciton Mott transition in GaN/(AlGa)N nanostructures

Author

Benjamin Damilano, Thierry Guillet, M. Vladimirova, Pierre Lefebvre, François Chiaruttini, S. Cronenberger, Denis Scalbert, Christelle Brimont, Benoit Jouault, Laboratoire Charles Coulomb (L2C), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Centre de recherche sur l'hétéroepitaxie et ses applications (CRHEA), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), and COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA)

Subjects
Photoluminescence, Materials science, Exciton, FOS: Physical sciences, 02 engineering and technology, 01 natural sciences, Condensed Matter::Materials Science, Mesoscale and Nanoscale Physics (cond-mat.mes-hall), 0103 physical sciences, [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, 010306 general physics, Quantum well, Condensed Matter::Quantum Gases, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], Condensed Matter - Mesoscale and Nanoscale Physics, Condensed matter physics, Condensed Matter::Other, 021001 nanoscience & nanotechnology, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, Magnetic field, Mott transition, Dipole, Quantum Gases (cond-mat.quant-gas), [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, Diamagnetism, Condensed Matter - Quantum Gases, 0210 nano-technology, Excitation
Abstract

The Mott transition from a dipolar excitonic liquid to an electron-hole plasma is demonstrated in a wide GaN/(Al,Ga)N quantum well at $T=7$K by means of spatially-resolved magneto-photoluminescence spectroscopy. Increasing optical excitation density we drive the system from the excitonic state, characterized by a diamagnetic behavior and thus a quadratic energy dependence on the magnetic field, to the unbound electron-hole state, characterized by a linear shift of the emission energy with the magnetic field. The complexity of the system requires to take into account both the density-dependence of the exciton binding energy and the exciton-exciton interaction and correlation energy that are of the same order of magnitude. We estimate the carrier density at Mott transition as $n_\mathrm{Mott}\approx 2\times 10^{11}$cm$^{-2}$ and address the role played by excitonic correlations in this process. Our results strongly rely on the spatial resolution of the photoluminescence and the assessment of the carrier transport. We show, that in contrast to GaAs/(Al,Ga)As systems, where transport of dipolar magnetoexcitons is strongly quenched by the magnetic field due to exciton mass enhancement, in GaN/(Al,Ga)N the band parameters are such that the transport is preserved up to $9$T., Comment: 15 pages 13 figures

Published
2021

2. Strong Coupling of Exciton-Polaritons in a Bulk GaN Planar Waveguide: Quantifying the Coupling Strength

Author

Thierry Guillet, Pierre Disseix, Blandine Alloing, Laetitia Doyennette, Edmond Cambril, Jesús Zúñiga-Pérez, M. Gromovyi, Stephanie Rennesson, G. Kreyder, F. Médard, Fabrice Semond, Joël Leymarie, Sophie Bouchoule, François Réveret, and Christelle Brimont

Subjects
Coupling, Physics, Photon, Condensed matter physics, Exciton, Physics::Optics, General Physics and Astronomy, 02 engineering and technology, Dielectric, Exciton-polaritons, 021001 nanoscience & nanotechnology, 01 natural sciences, law.invention, law, Ellipsometry, 0103 physical sciences, Polariton, 010306 general physics, 0210 nano-technology, Waveguide
Abstract

We investigate the demonstration and quantification of the strong coupling between excitons and guided photons in a GaN slab waveguide. The dispersions of waveguide polaritons are measured from T = 6 to 300 K through gratings. They are carefully analyzed within four models based on different assumptions, in order to assess the strong-coupling regime. We prove that the guided photons and excitons are strongly coupled at all investigated temperatures, with a small (11%) dependence on the temperature. However, the values of the Rabi splitting strongly vary among the four models: the "coupled oscillator" model overestimates the coupling; the analytical "Elliott-Tanguy" model precisely describes the dielectric susceptibility of GaN near the excitonic transition, leading to a Rabi splitting equal to 82 ± 10 meV for fundamental transverse-electric mode; the experimental ellipsometry-based model leads to smaller values of 55 ± 6 meV. We evidence that, for waveguides including active layers with large oscillator strengths, as required for room-temperature polaritonic devices, a strong bending of the modes' dispersion is not necessarily the signature of the strong coupling, which requires for its reliable assessment a precise analysis of the material dielectric susceptibility.

Published
2020

3. Monolithic integration of ultraviolet microdisk lasers into photonic circuits in a III-nitride-on-silicon platform

Author

Benjamin Damilano, Blandine Alloing, Laetitia Doyennette, Fabrice Semond, Hassen Souissi, Farsane Tabataba-Vakili, Xavier Checoury, Bruno Gayral, Christelle Brimont, Eric Frayssinet, Jean-Yves Duboz, Philippe Boucaud, Thierry Guillet, Sébastien Chenot, Moustafa El Kurdi, Centre de Nanosciences et de Nanotechnologies (C2N), Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Centre de recherche sur l'hétéroepitaxie et ses applications (CRHEA), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), Laboratoire Charles Coulomb (L2C), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), ANR-17-CE08-0043,MILAGAN,Laser microdisque en (Al,Ga,In)-N injecté électriquement(2017), and Université Nice Sophia Antipolis (... - 2019) (UNS)

Subjects
Materials science, Silicon, chemistry.chemical_element, FOS: Physical sciences, Gallium nitride, 02 engineering and technology, Applied Physics (physics.app-ph), Nitride, Grating, 01 natural sciences, 7. Clean energy, Waveguide (optics), law.invention, 010309 optics, chemistry.chemical_compound, law, 0103 physical sciences, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], business.industry, Physics - Applied Physics, 021001 nanoscience & nanotechnology, Laser, Atomic and Molecular Physics, and Optics, chemistry, Optoelectronics, Photonics, 0210 nano-technology, business, Lasing threshold
Abstract

Ultraviolet microdisk lasers are integrated monolithically into photonic circuits using a III-nitride-on-silicon platform with gallium nitride (GaN) as the main waveguide layer. The photonic circuits consist of a microdisk and a pulley waveguide, terminated by out-coupling gratings. In this Letter, we measure quality factors up to 3500 under continuous-wave excitation. Lasing is observed from 374 to 399 nm under pulsed excitation, achieving low-threshold energies of 0.14 m J / c m 2 per pulse (threshold peak powers of 35 k W / c m 2 ). A large peak-to-background dynamic of around 200 is observed at the out-coupling grating for small gaps of 50 nm between the disk and the waveguide. These devices operate at the limit of what can be achieved with GaN in terms of operation wavelength.

Published
2020
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4. Demonstration of critical coupling in an active III-nitride microdisk photonic circuit on silicon

Author

Benjamin Damilano, Christelle Brimont, Stephanie Rennesson, Sébastien Sauvage, Thierry Guillet, Moustafa El Kurdi, Xavier Checoury, Fabrice Semond, Philippe Boucaud, Jean-Yves Duboz, Farsane Tabataba-Vakili, Eric Frayssinet, Laetitia Doyennette, Bruno Gayral, Centre de Nanosciences et Nanotechnologies (C2N (UMR_9001)), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Nanophysique et Semiconducteurs (NPSC), PHotonique, ELectronique et Ingénierie QuantiqueS (PHELIQS), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire Charles Coulomb (L2C), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Centre de recherche sur l'hétéroepitaxie et ses applications (CRHEA), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), Université Nice Sophia Antipolis (1965 - 2019) (UNS), and ANR-17-CE08-0043,MILAGAN,Laser microdisque en (Al,Ga,In)-N injecté électriquement(2017)

Subjects
Materials science, Silicon, lcsh:Medicine, FOS: Physical sciences, chemistry.chemical_element, Physics::Optics, Applied Physics (physics.app-ph), 02 engineering and technology, Nitride, 7. Clean energy, 01 natural sciences, Article, 010309 optics, 0103 physical sciences, Lasers, LEDs and light sources, Spontaneous emission, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], lcsh:Science, Electronic circuit, Semiconductor lasers, Coupling, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], Multidisciplinary, business.industry, lcsh:R, Physics - Applied Physics, 021001 nanoscience & nanotechnology, 3. Good health, Microresonators, Optics and photonics, chemistry, Optoelectronics, lcsh:Q, Photonics, Whispering-gallery wave, 0210 nano-technology, business, Lasing threshold, Physics - Optics, Optics (physics.optics)
Abstract

On-chip microlaser sources in the blue constitute an important building block for complex integrated photonic circuits on silicon. We have developed photonic circuits operating in the blue spectral range based on microdisks and bus waveguides in III-nitride on silicon. We report on the interplay between microdisk-waveguide coupling and its optical properties. We observe critical coupling and phase matching, i.e. the most efficient energy transfer scheme, for very short gap sizes and thin waveguides (g = 45 nm and w = 170 nm) in the spontaneous emission regime. Whispering gallery mode lasing is demonstrated for a wide range of parameters with a strong dependence of the threshold on the loaded quality factor. We show the dependence and high sensitivity of the output signal on the coupling. Lastly, we observe the impact of processing on the tuning of mode resonances due to the very short coupling distances. Such small footprint on-chip integrated microlasers providing maximum energy transfer into a photonic circuit have important potential applications for visible-light communication and lab-on-chip bio-sensors., Comment: 10 pages, 6 figures, supplementary: 6 pages, 8 figures

Published
2019

5. Blue Microlasers Integrated on a Photonic Platform on Silicon

Author

Jean-Yves Duboz, Xavier Checoury, Christelle Brimont, Benjamin Damilano, Fabrice Semond, Philippe Boucaud, Farsane Tabataba-Vakili, Thierry Guillet, Moustafa El Kurdi, Stephanie Rennesson, Sébastien Sauvage, Eric Frayssinet, Iännis Roland, Laetitia Doyennette, Bruno Gayral, Centre de Nanosciences et de Nanotechnologies [Orsay] (C2N), Université Paris-Sud - Paris 11 (UP11)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Nanophysique et Semiconducteurs (NPSC), PHotonique, ELectronique et Ingénierie QuantiqueS (PHELIQS), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire Charles Coulomb (L2C), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Centre de recherche sur l'hétéroepitaxie et ses applications (CRHEA), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), ANR Quanonic, ANR Milagan, Labex Ganex, ANR-17-CE08-0043,MILAGAN,Laser microdisque en (Al,Ga,In)-N injecté électriquement(2017), ANR-11-LABX-0014,GANEX,Réseau national sur GaN(2011), ANR-13-BS10-0010,QUANONIC,Optique quantique et non-linéaire dans des cavités nitrures(2013), and Université Nice Sophia Antipolis (1965 - 2019) (UNS)

Subjects
Materials science, Nanophotonics, FOS: Physical sciences, Physics::Optics, Applied Physics (physics.app-ph), 02 engineering and technology, Grating, 01 natural sciences, law.invention, 010309 optics, law, 0103 physical sciences, Electrical and Electronic Engineering, Quantum well, business.industry, Physics - Applied Physics, 021001 nanoscience & nanotechnology, Laser, Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], Optoelectronics, Whispering-gallery wave, Photonics, 0210 nano-technology, business, Waveguide, Lasing threshold, Biotechnology
Abstract

International audience; The main interest of group-III-nitride nanophotonic circuits is the integration of active structures and laser sources. A photonic platform of group-III-nitride microdisk lasers integrated on silicon and emitting in the blue spectral range is demonstrated. The active microdisks are side-coupled to suspended bus waveguides, and the coupled emission is guided and outcoupled to free space using grating couplers. A small gap size of less than 100 nm between the disk and the waveguide is required in the blue spectral range for optimal evanescent coupling. To avoid reabsorption of the microdisk emission in the waveguide, the quantum wells are etched away from the waveguide. Under continuous-wave excitation, loaded quality factors greater than 2000 are observed for the whispering gallery modes for devices with small gaps and large waveguide bending angles. Under pulsed excitation conditions, lasing is evidenced for 3 μm diameter microdisks integrated in a full photonic circuit. We thus present a first demonstration of a III-nitride microlaser coupled to a nanophotonic circuit.

Published
2018

6. Competition between horizontal and vertical polariton lasing in planar microcavities

Author

Pierre Disseix, Joël Leymarie, Jesús Zúñiga-Pérez, Guillaume Malpuech, O. Jamadi, Fabrice Semond, Xavier Lafosse, Léo Mallet-Dida, Mathieu Leroux, Thierry Guillet, Sophie Bouchoule, Dmitry Solnyshkov, Christelle Brimont, François Réveret, Institut Pascal (IP), SIGMA Clermont (SIGMA Clermont)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique des Lasers, Atomes et Molécules - UMR 8523 (PhLAM), Université de Lille-Centre National de la Recherche Scientifique (CNRS), Laboratoire Charles Coulomb (L2C), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Centre de Nanosciences et de Nanotechnologies [Orsay] (C2N), Université Paris-Sud - Paris 11 (UP11)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Centre de recherche sur l'hétéroepitaxie et ses applications (CRHEA), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), ANR-16-IDEX-0001,CAP 20-25,CAP 20-25(2016), and Université Nice Sophia Antipolis (... - 2019) (UNS)

Subjects
Physics, Condensed Matter::Quantum Gases, Total internal reflection, Photon, Condensed Matter - Mesoscale and Nanoscale Physics, Scattering, Condensed Matter::Other, Exciton, FOS: Physical sciences, Physics::Optics, 02 engineering and technology, 021001 nanoscience & nanotechnology, 01 natural sciences, Molecular physics, Light cone, [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, Radiative transfer, Polariton, 010306 general physics, 0210 nano-technology, Lasing threshold, Optics (physics.optics), Physics - Optics
Abstract

International audience; Planar microcavities filled with active materials containing excitonic resonances host radiative exciton-polariton (polariton) modes with in-plane wave vectors within the light cone. They also host at least one mode that is guided in the cavity plane by total internal reflection and that is not radiatively coupled to the vacuum modes except through defects or sample edges. We show that polariton lasing mediated by polariton stimulated scattering can occur concomitantly in both types of modes in a microcavity. By adjusting the detuning between the exciton and the radiative photon mode one can favor polariton lasing either in the radiative or in the guided modes. Our results suggest that the competition between these two types of polariton lasing modes may have played a role in many previous observations of polariton lasing and polariton Bose-Einstein condensation.

Published
2019

7. III-nitride on silicon electrically injected microrings for nanophotonic circuits

Author

Stephanie Rennesson, Sébastien Sauvage, Philippe Boucaud, Benjamin Damilano, Thierry Guillet, Fabrice Semond, Bruno Gayral, Xavier Checoury, Farsane Tabataba-Vakili, Moustafa El Kurdi, Christelle Brimont, Laetitia Doyennette, Iännis Roland, Jean-Yves Duboz, Eric Frayssinet, Raffaele Colombelli, Bruno Paulillo, Centre de Nanosciences et de Nanotechnologies [Orsay] (C2N), Université Paris-Sud - Paris 11 (UP11)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Nanophysique et Semiconducteurs (NPSC), PHotonique, ELectronique et Ingénierie QuantiqueS (PHELIQS), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Centre de recherche sur l'hétéroepitaxie et ses applications (CRHEA), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), Laboratoire Charles Coulomb (L2C), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Université Nice Sophia Antipolis (1965 - 2019) (UNS), and ANR-17-CE08-0043,MILAGAN,Laser microdisque en (Al,Ga,In)-N injecté électriquement(2017)

Subjects
Materials science, Silicon, Nanophotonics, chemistry.chemical_element, FOS: Physical sciences, 02 engineering and technology, Applied Physics (physics.app-ph), Electroluminescence, 01 natural sciences, 010309 optics, 0103 physical sciences, [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, Electronic circuit, Power density, business.industry, Direct current, Physics - Applied Physics, 021001 nanoscience & nanotechnology, Atomic and Molecular Physics, and Optics, chemistry, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], Optoelectronics, Photonics, 0210 nano-technology, business, Lasing threshold
Abstract

International audience; Nanophotonic circuits using group III-nitrides on silicon are still lacking one key component: efficient electrical injection. In this paper we demonstrate an electrical injection scheme using a metal microbridge contact in thin III-nitride on silicon mushroom-type microrings that is compatible with integrated nanophotonic circuits with the goal of achieving electrically injected lasing. Using a central buried n-contact to bypass the insulating buffer layers, we are able to underetch the microring, which is essential for maintaining vertical confinement in a thin disk. We demonstrate direct current room-temperature electroluminescence with 440 mW/cm 2 output power density at 20 mA from such microrings with diameters of 30 to 50 µm. The first steps towards achieving an integrated photonic circuit are demonstrated.

Published
2019

8. Q factor limitation at short wavelength (around 300 nm) in III-nitride-on-silicon photonic crystal cavities

Author

Jean-Yves Duboz, Xavier Checoury, Fabrice Semond, Moustafa El Kurdi, Thierry Guillet, Philippe Boucaud, Iännis Roland, Stephanie Rennesson, Sébastien Sauvage, Farsane Tabataba-Vakili, Christelle Brimont, Bruno Gayral, Thi-Mo Tran, Centre de Nanosciences et de Nanotechnologies [Orsay] (C2N), Université Paris-Sud - Paris 11 (UP11)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Laboratoire Charles Coulomb (L2C), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Centre de recherche sur l'hétéroepitaxie et ses applications (CRHEA), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), Nanophysique et Semiconducteurs (NPSC), PHotonique, ELectronique et Ingénierie QuantiqueS (PHELIQS), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), ANR-11-LABX-0014,GANEX,Réseau national sur GaN(2011), ANR-13-BS10-0010,QUANONIC,Optique quantique et non-linéaire dans des cavités nitrures(2013), ANR-11-IDEX-0003,IPS,Idex Paris-Saclay(2011), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Saclay, and Université Nice Sophia Antipolis (... - 2019) (UNS)

Subjects
010302 applied physics, Materials science, Silicon photonics, Physics and Astronomy (miscellaneous), Silicon, business.industry, chemistry.chemical_element, FOS: Physical sciences, 02 engineering and technology, Physics - Applied Physics, Applied Physics (physics.app-ph), Nitride, 021001 nanoscience & nanotechnology, 01 natural sciences, Crystal, chemistry, Q factor, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], 0103 physical sciences, Optoelectronics, 0210 nano-technology, business, Absorption (electromagnetic radiation), Quantum well, Photonic crystal
Abstract

International audience; III-nitride-on-silicon L3 and H2 photonic crystal cavities with resonances down to 315 nm and quality factors up to 1085 at 337 nm have been demonstrated. The reduction of quality factor (Q) with decreasing wavelength is investigated. Besides the QW absorption below 340 nm a noteworthy contribution is attributed to the residual absorption present in thin AlN layers grown on silicon, as measured by spectroscopic ellipsometry. This residual absorption ultimately limits the Q factor to around 250 at 300 nm when no active layer is present.

Published
2019
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9. Polariton condensates at room temperature

Author

Thierry Guillet, Christelle Brimont, Laboratoire Charles Coulomb (L2C), and Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Oscillator strength, Band gap, Exciton, FOS: Physical sciences, Physics::Optics, Energy Engineering and Power Technology, 02 engineering and technology, Physics and Astronomy(all), 01 natural sciences, GaN, Mesoscale and Nanoscale Physics (cond-mat.mes-hall), 0103 physical sciences, Polariton, 010306 general physics, Condensate, Condensed Matter::Quantum Gases, Physics, Condensed Matter - Mesoscale and Nanoscale Physics, Condensed matter physics, Condensed Matter::Other, Condensation, General Engineering, 021001 nanoscience & nanotechnology, Organic semiconductor, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], ZnO, Relaxation (physics), Microcavity, 0210 nano-technology, Excitation, Optics (physics.optics), Physics - Optics
Abstract

We review the recent developments of the polariton physics in microcavities featuring the exciton-photon strong coupling at room-temperature, and leading to the achievement of room-temperature polariton condensates. Such cavities embed active layers with robust excitons that present a large binding energy and a large oscillator strength, i.e. wide bandgap inorganic or organic semiconductors, or organic molecules. These various systems are compared, in terms of figures of merit and of common features related to their strong oscillator strength. The various demonstrations of polariton laser are compared, as well as their condensation phase diagrams. The room-temperature operation indeed allows a detailed investigation of the thermodynamic and out-of-equilibrium regimes of the condensation process. The crucial role of the spatial dynamics of the condensate formation is discussed, as well as the debated issue of the mechanism of stimulated relaxation from the reservoir to the condensate under non-resonant excitation. Finally the prospects of polariton devices are presented., 22 pages, 3 figures, 1 table

Published
2016

10. Imaging of Photonic Crystal Localized Modes through Third-Harmonic Generation

Author

Christelle Brimont, Xavier Checoury, Bruno Gayral, Y. Zeng, Iännis Roland, Sébastien Sauvage, Philippe Boucaud, Moustafa El Kurdi, Thierry Guillet, Fabrice Semond, Zheng Han, Institut d'électronique fondamentale (IEF), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Nanophysique et Semiconducteurs (NPSC), PHotonique, ELectronique et Ingénierie QuantiqueS (PHELIQS), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire Charles Coulomb (L2C), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Centre de recherche sur l'hétéroepitaxie et ses applications (CRHEA), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), ANR-13-BS10-0010,QUANONIC,Optique quantique et non-linéaire dans des cavités nitrures(2013), and Université Nice Sophia Antipolis (1965 - 2019) (UNS)

Subjects
Materials science, Physics::Optics, 02 engineering and technology, 01 natural sciences, law.invention, third-harmonic generation, 010309 optics, Optics, Optical microscope, law, 0103 physical sciences, Microscopy, Electrical and Electronic Engineering, Photonic crystal, III-nitride semiconductors, business.industry, Resolution (electron density), 021001 nanoscience & nanotechnology, Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], Harmonics, Excited state, Optoelectronics, Photonics, subwavelength imaging, 0210 nano-technology, business, photonic crystal, Excitation, Biotechnology
Abstract

International audience; We demonstrate high-spatial resolution imaging of localized cavity modes through third-harmonic frequency conversion. The experiments are performed with a III-nitrideon-silicon photonic platform. The resonant cavities are formed within suspended two-dimensional photonic crystals and are excited with a continuous-wave excitation around 1550 nm. The III-nitride materials (GaN and AlN) are transparent for both pump and harmonics. The third-harmonic nonlinear process allows one to indirectly observe the fundamental confined cavity mode with spatial profiles equivalent to those usually obtained by local probe microscopy techniques such as scanning near-field optical microscopy. An excellent agreement is obtained between the measured polarization-resolved third harmonic emission patterns and those calculated through the third-order nonlinear polarization. We show that the spatial profiles of the radiated patterns are strongly dependent on defocusing, thus highlighting the strong sensitivity of the imaging.

Published
2016

11. III-Nitride on silicon photonic circuits

Author

Farsane Tabataba-Vakili, Thierry Guillet, M. P. De Micheli, Stephanie Rennesson, Sébastien Sauvage, Julien Selles, Xavier Checoury, Iännis Roland, Christelle Brimont, Jean-Yves Duboz, Bruno Gayral, M. El Kurdi, Philippe Boucaud, Y. Zeng, M. Gromovyi, and Fabrice Semond

Subjects
010302 applied physics, Materials science, Silicon photonics, Silicon, business.industry, Photonic integrated circuit, Physics::Optics, chemistry.chemical_element, Gallium nitride, 02 engineering and technology, 021001 nanoscience & nanotechnology, 01 natural sciences, Yablonovite, Condensed Matter::Materials Science, chemistry.chemical_compound, Resonator, chemistry, 0103 physical sciences, Electronic engineering, Optoelectronics, Photonics, 0210 nano-technology, business, Photonic crystal
Abstract

We present recent progress achieved with III-nitride photonic circuits epitaxially grown on silicon(111). The photonic circuits embed two-dimensional photonic crystals and microdisk resonators coupled to suspended waveguides. We discuss the linear and nonlinear response of the resonators through second and third harmonic generation.

Published
2017

12. Transient photoluminescence of aluminum-rich (Al,Ga)N low-dimensional structures

Author

Pierre Valvin, Christelle Brimont, Pierre Lefebvre, Kazumasa Hiramatsu, Hideto Miyake, and Bernard Gil

Subjects
Photoluminescence, Materials science, chemistry.chemical_element, 02 engineering and technology, Nitride, 01 natural sciences, Aluminium, 0103 physical sciences, Materials Chemistry, Ultraviolet light, Electrical and Electronic Engineering, 010302 applied physics, Condensed matter physics, business.industry, Surfaces and Interfaces, Nanosecond, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Crystallographic defect, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, Semiconductor, chemistry, Quantum efficiency, 0210 nano-technology, business
Abstract

Light-emitting devices based on high-Al content (Al,Ga)N suffer from high densities of dislocations or other point defects, counterbalanced by the carrier localization arising from disorder in the ternary alloy. One way to improve the internal quantum efficiency is the controlled Si-doping of AlxGa1−xN/AlyGa1−yN multi-quantum wells, which was assigned to the reduction of point defects by reduction of internal strains, for some ideal concentration of Si. Time-resolved photoluminescence (TR-PL) can be used [S. F. Chichibu et al., Appl. Phys. Lett. 99, 051902 (2011)] to try and correlate the observed PL time-decays with the density of defects, in relation with the nonradiative recombination probability of photoexcited carriers. We present TR-PL studies of MOVPE-grown Si-doped AlxGa1−xN/AlyGa1−yN multi-quantum wells with typical values of x = 0.6 and y = 0.7 and of AlxGa1−xN epilayers with x up to 0.86. High-Al content MQWs and epilayers exhibit similar bi-exponential PL decay dynamics, with the slower component rapidly quenched when T is increased. The fast decay component remains in the nanosecond range at all temperatures and the PL intensity loss is limited by carrier localization.

Published
2014

13. III-Nitride-on-silicon microdisk lasers from the blue to the deep ultra-violet

Author

Thierry Guillet, Iännis Roland, Julien Selles, M. El Kurdi, V. Crepel, Benjamin Damilano, Fabrice Semond, Philippe Boucaud, Bruno Gayral, Meletios Mexis, Xavier Checoury, Stephanie Rennesson, Christelle Brimont, Mathieu Leroux, Matière et Systèmes Complexes (MSC (UMR_7057)), Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Charles Coulomb (L2C), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Centre de recherche sur l'hétéroepitaxie et ses applications (CRHEA), Université Nice Sophia Antipolis (... - 2019) (UNS), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Nanophysique et Semiconducteurs (NPSC), PHotonique, ELectronique et Ingénierie QuantiqueS (PHELIQS), Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), ANR-13-BS10-0010,QUANONIC,Optique quantique et non-linéaire dans des cavités nitrures(2013), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Matière et Systèmes Complexes (MSC), and Université Nice Sophia Antipolis (1965 - 2019) (UNS)

Subjects
Materials science, Physics and Astronomy (miscellaneous), Physics::Optics, 02 engineering and technology, 7. Clean energy, 01 natural sciences, law.invention, Optical pumping, Resonator, Condensed Matter::Materials Science, Optics, law, 0103 physical sciences, 010302 applied physics, business.industry, Quantum-confined Stark effect, Wide-bandgap semiconductor, 021001 nanoscience & nanotechnology, Laser, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], Optoelectronics, Photonics, 0210 nano-technology, business, Ternary operation, Lasing threshold
Abstract

We present a series of microdisk lasers realized within the same GaN-on-Si photonic platform scheme, and operating at room temperature under pulsed optical pumping over a broad spectral range extending over λ = 275 nm–470 nm. The III-nitride microdisks embed either binary GaN/AlN multiple quantum wells (MQWs) for UV operation, or ternary InGaN/GaN MQWs for violet and blue operation. This demonstrates the versatility of this nitride-on-silicon platform, and the realization on this platform of efficient active layers for lasing action over a 200 nm broad UV to visible spectral range. We probe the lasing threshold carrier density over the whole spectral range and found that it is similar whatever the emission wavelength for these Q > 1000 microdisk resonators with a constant material quality until quantum confined Stark effect takes over. The threshold is also found independent of microdisk diameters from 3 to 12 μm, with a β factor intermediate between the one of vertical cavity lasers and the one of small modal volume “thresholdless” lasers.

Published
2016

14. Phase-matched second harmonic generation with on-chip GaN-on-Si microdisks

Author

M. P. De Micheli, Sébastien Sauvage, Philippe Boucaud, Jean-Yves Duboz, M. Gromovyi, Xavier Checoury, Iännis Roland, Fabrice Semond, M. El Kurdi, Thierry Guillet, Bruno Gayral, Y. Zeng, Christelle Brimont, Institut d'électronique fondamentale (IEF), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Centre de recherche sur l'hétéroepitaxie et ses applications (CRHEA), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), Laboratoire Charles Coulomb (L2C), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Nanophysique et Semiconducteurs (NPSC), PHotonique, ELectronique et Ingénierie QuantiqueS (PHELIQS), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire de physique de la matière condensée (LPMC), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS), ANR-13-BS10-0010,QUANONIC,Optique quantique et non-linéaire dans des cavités nitrures(2013), ANR-11-LABX-0014,GANEX,Réseau national sur GaN(2011), Université Nice Sophia Antipolis (... - 2019) (UNS), Institut de Physique de Nice (INPHYNI), Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA), ANR-11-IDEX-0003,IPS,Idex Paris-Saclay(2011), and Centre National de la Recherche Scientifique (CNRS)-Université Nice Sophia Antipolis (... - 2019) (UNS)

Subjects
Materials science, Silicon, Phase (waves), chemistry.chemical_element, Physics::Optics, Gallium nitride, 02 engineering and technology, 01 natural sciences, Article, [SPI.MAT]Engineering Sciences [physics]/Materials, 010309 optics, chemistry.chemical_compound, 0103 physical sciences, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], Multidisciplinary, business.industry, Second-harmonic generation, 021001 nanoscience & nanotechnology, chemistry, Excited state, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, Continuous wave, Optoelectronics, Whispering-gallery wave, Photonics, 0210 nano-technology, business
Abstract

We demonstrate phase-matched second harmonic generation in gallium nitride on silicon microdisks. The microdisks are integrated with side-coupling bus waveguides in a two-dimensional photonic circuit. The second harmonic generation is excited with a continuous wave laser in the telecom band. By fabricating a series of microdisks with diameters varying by steps of 8 nm, we obtain a tuning of the whispering gallery mode resonances for the fundamental and harmonic waves. Phase matching is obtained when both resonances are matched with modes satisfying the conservation of orbital momentum, which leads to a pronounced enhancement of frequency conversion.

Published
2016

15. Near-infrared III-nitride-on-silicon nanophotonic platform with microdisk resonators

Author

Christelle Brimont, M. Gromovyi, M. P. De Micheli, Xavier Checoury, Fabrice Semond, Philippe Boucaud, Iännis Roland, M. El Kurdi, Bruno Gayral, Y. Zeng, Jean-Yves Duboz, Sébastien Sauvage, Thierry Guillet, Institut d'électronique fondamentale (IEF), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Charles Coulomb (L2C), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Nanophysique et Semiconducteurs (NPSC), PHotonique, ELectronique et Ingénierie QuantiqueS (PHELIQS), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Centre de recherche sur l'hétéroepitaxie et ses applications (CRHEA), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), Institut Non Linéaire de Nice Sophia-Antipolis (INLN), Centre National de la Recherche Scientifique (CNRS)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA), Laboratoire de physique de la matière condensée (LPMC), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA), ANR-13-BS10-0010,QUANONIC,Optique quantique et non-linéaire dans des cavités nitrures(2013), Université Nice Sophia Antipolis (1965 - 2019) (UNS), and COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Materials science, Silicon, business.industry, Photonic integrated circuit, Nanophotonics, Second-harmonic generation, Resonance, chemistry.chemical_element, 02 engineering and technology, 021001 nanoscience & nanotechnology, 01 natural sciences, Atomic and Molecular Physics, and Optics, law.invention, 010309 optics, Resonator, Optics, chemistry, law, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], 0103 physical sciences, Optoelectronics, Whispering-gallery wave, 0210 nano-technology, business, Waveguide
Abstract

International audience; We have developed a nanophotonic platform with microdisks using epitaxial III-nitride materials on silicon. The two-dimensional platform consists of suspended waveguides and mushroom-type microdisks as resonators side-coupled with a bus waveguide. Loaded quality factors up to 80000 have been obtained in the near-infrared spectral range for microdisk diameters between 8 and 15 μm. We analyze the dependence of the quality factors as a function of coupling efficiency. We have performed continuous-wave second harmonic generation experiments in resonance with the whispering gallery modes supported by the microdisks.

Published
2016

16. Picosecond dynamics of free and bound excitons in doped diamond

Author

Pierre Lefebvre, Marie-Amandine Pinault-Thaury, Julien Barjon, Pierre Valvin, Alexandre Tallaire, François Jomard, Ovidiu Brinza, Jocelyn Achard, Christelle Brimont, Groupe d'Etude de la Matière Condensée (GEMAC), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Charles Coulomb (L2C), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Laboratoire des Sciences des Procédés et des Matériaux (LSPM), Centre National de la Recherche Scientifique (CNRS)-Université Sorbonne Paris Cité (USPC)-Institut Galilée-Université Paris 13 (UP13), DIAMONIX and DIAMONIX2 French research projects, approved by the competitiveness cluster of Aerospace Valley and funded by the Unique Interministerial Fund (FUI)., and Miloš Nesládek

Subjects
Materials science, Photoluminescence, Exciton, chemistry.chemical_element, 02 engineering and technology, engineering.material, 01 natural sciences, 7. Clean energy, Condensed Matter::Materials Science, symbols.namesake, Condensed Matter::Superconductivity, 0103 physical sciences, Physics::Atomic and Molecular Clusters, [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, Boron, Biexciton, 010302 applied physics, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], Auger effect, Condensed Matter::Other, Doping, Diamond, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, 021001 nanoscience & nanotechnology, chemistry, Picosecond, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, engineering, symbols, Atomic physics, 0210 nano-technology
Abstract

International audience; The dynamics of the free-exciton capture by boron acceptors and phosphorus donors in diamond is observed in the picosecond range by time-resolved photoluminescence experiments at low temperature. The formation of boron-bound excitons is observed with a delay of 410 ps after the formation of free excitons. For phosphorus, this delay is 120 ps. This is the result of the free-exciton capture by B0 and P0 impurities. The lifetimes of boron- and phosphorus-bound excitons are measured and found to be equal to 270 and 70 ps, respectively. These values are about four orders of magnitude shorter than for the same impurities in silicon. Ei being the ionization energy of dopants, these results scale well with the E4i dependence of the Auger recombination rate expected for bound excitons in indirect band-gap semiconductors.

Published
2016

17. Deep-UV nitride-on-silicon microdisk lasers

Author

Guillaume Cassabois, Christelle Brimont, Thierry Guillet, Meletios Mexis, Iännis Roland, Y. Zeng, Xavier Checoury, Pierre Valvin, Fabrice Semond, Philippe Boucaud, Bruno Gayral, Julien Selles, Laboratoire Charles Coulomb (L2C), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Institut d'électronique fondamentale (IEF), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Centre de recherche sur l'hétéroepitaxie et ses applications (CRHEA), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), Nanophysique et Semiconducteurs (NPSC), PHotonique, ELectronique et Ingénierie QuantiqueS (PHELIQS), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), ANR-13-BS10-0010,QUANONIC,Optique quantique et non-linéaire dans des cavités nitrures(2013), ANR-11-LABX-0014,GANEX,Réseau national sur GaN(2011), and Université Nice Sophia Antipolis (... - 2019) (UNS)

Subjects
010302 applied physics, Multidisciplinary, Materials science, Silicon, business.industry, chemistry.chemical_element, 02 engineering and technology, Substrate (electronics), Nitride, 021001 nanoscience & nanotechnology, 7. Clean energy, 01 natural sciences, Article, Active layer, chemistry, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], 0103 physical sciences, Sapphire, Optoelectronics, Spontaneous emission, Photonics, 0210 nano-technology, business, Quantum well
Abstract

Deep ultra-violet semiconductor lasers have numerous applications for optical storage and biochemistry. Many strategies based on nitride heterostructures and adapted substrates have been investigated to develop efficient active layers in this spectral range, starting with AlGaN quantum wells on AlN substrates and more recently sapphire and SiC substrates. Here we report an efficient and simple solution relying on binary GaN/AlN quantum wells grown on a thin AlN buffer layer on a silicon substrate. This active region is embedded in microdisk photonic resonators of high quality factors and allows the demonstration of a deep ultra-violet microlaser operating at 275 nm at room temperature under optical pumping, with a spontaneous emission coupling factor β = (4 ± 2) 10−4. The ability of the active layer to be released from the silicon substrate and to be grown on silicon-on-insulator substrates opens the way to future developments of nitride nanophotonic platforms on silicon.

Published
2016

18. Non‐linear emission properties of ZnO microcavities

Author

Jesús Zúñiga-Pérez, Mathieu Leroux, Thierry Bretagnon, M. Mihailovic, Sophie Bouchoule, Bernard Gil, Fabrice Semond, Pierre Valvin, F. Médard, Thierry Guillet, Christelle Brimont, Laboratoire Charles Coulomb (L2C), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), ANR-06-BLAN-0135,ZOOM,Zinc Oxide Optical Microcavities(2006), and European Project: 235114,EC:FP7:PEOPLE,FP7-PEOPLE-ITN-2008,CLERMONT4(2009)

Subjects
Coupling, Materials science, Condensed matter physics, business.industry, Exciton, Physics::Optics, 02 engineering and technology, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, Vertical-cavity surface-emitting laser, Quality (physics), Planar, Interference (communication), [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], 0103 physical sciences, Optoelectronics, 010306 general physics, 0210 nano-technology, business, Lasing threshold, ComputingMilieux_MISCELLANEOUS, Excitation
Abstract

Lasing in a ZnO planar microcavity is reported under optical excitation up to room temperature. The cavity presents a quality factor of 450 and the simultaneous presence of two cavity modes with different interference orders. The transition from the strong coupling to the weak coupling regime is observed at lasing threshold. The gain mechanism below T = 240 K is attributed to excitons, according to the observation of a specific gain transition within the strong coupling regime. (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Published
2012

19. Optical investigations of nonpolar homoepitaxial ZnO/(Zn,Mg)O quantum wells

Author

Christelle Brimont, Thierry Guillet, Bernard Gil, M. Teisseire, Jean-Michel Chauveau, Luc Beaur, Dimitri Tainoff, and Thierry Bretagnon

Subjects
010302 applied physics, Photoluminescence, Condensed Matter::Other, Chemistry, Orthogonal polarization spectral imaging, Magnesium, Exciton, Analytical chemistry, chemistry.chemical_element, 02 engineering and technology, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, Spectral line, Condensed Matter::Materials Science, 0103 physical sciences, Continuous wave, 0210 nano-technology, Anisotropy, Quantum well
Abstract

We report growth of high quality ZnO/(Zn,Mg)O quantum wells, with 20% magnesium content, on M-plane oriented ZnO substrates. The optical properties are studied by reflectance spectroscopy and continuous wave photoluminescence. The reflectance spectra reveal strong in-plane optical anisotropies, as predicted by group theory. Signatures of confined excitons analogous to C-exciton in bulk ZnO, are detected using light polarized along the c-axis. Experiments performed in orthogonal polarization reveal confined states analogous to A and B bulk excitons. Envelope function calculations including excitonic interaction nicely match the experimental results. The weak Stokes-shift between reflectance and photoluminescence spectra, and clear reflectance structures, are evidences of good interface morphologies. The independency of intensity of the photoluminescence with the temperature indicates the very small contributions of non-radiative recombination channels in these samples (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Published
2012

20. Transport of dipolar excitons in (Al,Ga)N/GaN quantum wells

Author

Pierre Valvin, Nicolas Grandjean, Maria Vladimirova, P. Andreakou, Benoit Jouault, Thierry Bretagnon, Fedor Fedichkin, Thierry Guillet, Christelle Brimont, Pierre Lefebvre, Amélie Dussaigne, Laboratoire Charles Coulomb (L2C), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM), Centre de recherche sur l'hétéroepitaxie et ses applications (CRHEA), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), Commissariat à l'énergie atomique et aux énergies alternatives - Laboratoire d'Electronique et de Technologie de l'Information (CEA-LETI), 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), Institute of Condensed Matter Physics [Lausanne], Ecole Polytechnique Fédérale de Lausanne (EPFL), European Union Seventh Framework Programme, Grant No. PITN-GA-2011-289968., European Project: 289968,EC:FP7:PEOPLE,FP7-PEOPLE-2011-ITN,INDEX(2011), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), and Université Nice Sophia Antipolis (... - 2019) (UNS)

Subjects
Photoluminescence, Exciton, FOS: Physical sciences, 02 engineering and technology, 01 natural sciences, Condensed Matter::Materials Science, 0103 physical sciences, Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Spontaneous emission, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], 010306 general physics, Spectroscopy, Biexciton, Quantum well, Physics, Condensed Matter::Quantum Gases, Condensed Matter - Mesoscale and Nanoscale Physics, Condensed matter physics, Condensed Matter::Other, PACS: 71.35.−y, 78.67.Lt, 78.55.Cr, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, Electronic, Optical and Magnetic Materials, Blueshift, Quantum Gases (cond-mat.quant-gas), Condensed Matter - Quantum Gases, 0210 nano-technology, Excitation
Abstract

We investigate the transport of dipolar indirect excitons along the growth plane of polar (Al,Ga)N/GaN quantum well structures by means of spatially- and time-resolved photoluminescence spectroscopy. The transport in these strongly disordered quantum wells is activated by dipole-dipole repulsion. The latter induces an emission blue shift that increases linearly with exciton density, whereas the radiative recombination rate increases exponentially. Under continuous, localized excitation, we measure a continuous red shift of the emission, as excitons propagate away from the excitation spot. This shift corresponds to a steady-state gradient of exciton density, measured over several tens of micrometers. Time-resolved micro-photoluminescence experiments provide information on the dynamics of recombination and transport of dipolar excitons. We account for the ensemble of experimental results by solving the nonlinear drift-diffusion equation. Quantitative analysis suggests that in such structures, exciton propagation on the scale of 10 to 20 microns is mainly driven by diffusion, rather than by drift, due to the strong disorder and the presence of nonradiative defects. Secondary exciton creation, most probably by the intense higher-energy luminescence, guided along the sample plane, is shown to contribute to the exciton emission pattern on the scale up to 100 microns. The exciton propagation length is strongly temperature dependent, the emission being quenched beyond a critical distance governed by nonradiative recombination., Comment: 11 pages, 8 figures

Published
2015
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21. Near-infrared gallium nitride two-dimensional photonic crystal platform on silicon

Author

Zheng Han, S. Sauvage, Philippe Boucaud, Thierry Guillet, Fabrice Semond, Christelle Brimont, M. El Kurdi, A. Ghrib, Bruno Gayral, Y. Zeng, Candice Blin, Xavier Checoury, Iännis Roland, Institut d'électronique fondamentale (IEF), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Nanophysique et Semiconducteurs (NPSC), PHotonique, ELectronique et Ingénierie QuantiqueS (PHELIQS), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire Charles Coulomb (L2C), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Centre de recherche sur l'hétéroepitaxie et ses applications (CRHEA), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), ANR-13-BS10-0010,QUANONIC,Optique quantique et non-linéaire dans des cavités nitrures(2013), and Université Nice Sophia Antipolis (1965 - 2019) (UNS)

Subjects
Waveguide (electromagnetism), Materials science, Physics and Astronomy (miscellaneous), Silicon, business.industry, Wide-bandgap semiconductor, Physics::Optics, chemistry.chemical_element, Gallium nitride, 02 engineering and technology, Substrate (electronics), Nitride, 021001 nanoscience & nanotechnology, 01 natural sciences, 010309 optics, chemistry.chemical_compound, chemistry, Q factor, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], 0103 physical sciences, Optoelectronics, 0210 nano-technology, business, Photonic crystal
Abstract

International audience; We demonstrate a two-dimensional free-standing gallium nitride photonic crystal platform operating around 1550 nm and fabricated on a silicon substrate. Width-modulated waveguide cavities are integrated and exhibit loaded quality factors up to 34 000 at 1575 nm. We show the resonance tunability by varying the ratio of air hole radius to periodicity, and cavity hole displacement. We deduce a 7.9 dB/cm linear absorption loss for the suspended nitride structure from the power dependence of the cavity in-plane transmission.

Published
2014

22. Imaging of photonic modes in an AlN-based photonic crystal probed by an ultra-violet internal light source

Author

M. J. Rashid, Christelle Brimont, Bruno Gayral, Fabrice Semond, Thierry Guillet, Sylvain David, Delphine Néel, Xavier Checoury, Diane Sam-Giao, Sébastien Rousset, Philippe Boucaud, Laboratoire Charles Coulomb (L2C), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Institut d'électronique fondamentale (IEF), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Nanophysique et Semiconducteurs (NPSC), PHotonique, ELectronique et Ingénierie QuantiqueS (PHELIQS), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Centre de recherche sur l'hétéroepitaxie et ses applications (CRHEA), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), and Université Nice Sophia Antipolis (1965 - 2019) (UNS)

Subjects
Waveguide (electromagnetism), [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], Photon, Materials science, Spatial filter, business.industry, Guided-mode resonance, Physics::Optics, 02 engineering and technology, 021001 nanoscience & nanotechnology, 01 natural sciences, Yablonovite, Atomic and Molecular Physics, and Optics, Light scattering, Optics, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], 0103 physical sciences, Optoelectronics, Photonics, 010306 general physics, 0210 nano-technology, business, Photonic crystal
Abstract

International audience; The spatial distribution of photon modes confined in a 0D cavity and a 1D W1 waveguide is investigated on AlN-based photonic crystal (PC) membranes by spectrally resolved scanning confocal microscopy in the ultra-violet spectral range. The influence of the fabrication-induced disorder of the PC on the photon modes is analyzed. The cavity modes are shown to be robust with respect to disorder, whereas the 1D modes of the W1 waveguide are localized near its cut-off frequency. Those modifications of the lowest energy photonic modes are compared to simulations of weakly disordered photonic structures.

Published
2013

23. Phonon-assisted exciton formation in ZnO/(Zn, Mg)O single quantum wells grown on C-plane oriented substrates

Author

Luc Beaur, Thierry Bretagnon, Bernard Gil, Christian Morhain, Pierre Gilliot, Thierry Guillet, Christelle Brimont, Mathieu Gallart, Physique de l'Exciton, du Photon et du Spin (PEPS), Laboratoire Charles Coulomb (L2C), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-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)-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), Centre de recherche sur l'hétéroepitaxie et ses applications (CRHEA), Université Nice Sophia Antipolis (... - 2019) (UNS), and COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA)

Subjects
Photoluminescence, Phonon, Biophysics, 02 engineering and technology, 7. Clean energy, 01 natural sciences, Biochemistry, symbols.namesake, Condensed Matter::Materials Science, 0103 physical sciences, Photoluminescence excitation, 010306 general physics, Quantum well, Biexciton, Physics, Condensed Matter::Quantum Gases, Condensed matter physics, Condensed Matter::Other, Quantum-confined Stark effect, General Chemistry, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, Atomic and Molecular Physics, and Optics, Stark effect, symbols, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], 0210 nano-technology, Molecular beam epitaxy
Abstract

We report on absorption phenomena in ZnO/(Zn, Mg)O quantum wells grown along the c-axis by molecular beam epitaxy. The optical properties of such quantum wells are affected by a huge internal electric field. For wide quantum wells the absorption is driven by Quantum Confined Stark Effect. Phonon-assisted formation of excitons is observed in the case of thin quantum wells. The physical origin of these hot excitons is determined by using both low temperature ( T =10 K) photoluminescence excitation spectroscopy and reflectivity measurements.

Published
2013

24. From Excitonic to Photonic Polariton Condensate in a ZnO-Based Microcavity

Author

Gilles Patriarche, Christelle Brimont, Olfa Kamoun, Xavier Lafosse, Feng Li, Thierry Guillet, M. Mihailovic, Guillaume Malpuech, Jesús Zúñiga-Pérez, François Réveret, Meletios Mexis, Mathieu Leroux, Dimitri Solnyshkov, Sophie Bouchoule, Pierre Disseix, Laurent Orosz, Joël Leymarie, Centre de recherche sur l'hétéroepitaxie et ses applications (CRHEA), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), University of Sheffield [Sheffield], Laboratoire des sciences et matériaux pour l'électronique et d'automatique (LASMEA), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Centre National de la Recherche Scientifique (CNRS), Physique de l'Exciton, du Photon et du Spin (PEPS), Laboratoire Charles Coulomb (L2C), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de photonique et de nanostructures (LPN), Centre National de la Recherche Scientifique (CNRS), and Université Nice Sophia Antipolis (... - 2019) (UNS)

Subjects
Condensed Matter::Quantum Gases, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], Materials science, business.industry, Condensed Matter::Other, Condensation, General Physics and Astronomy, Physics::Optics, 02 engineering and technology, Substrate (electronics), 021001 nanoscience & nanotechnology, 7. Clean energy, 01 natural sciences, Condensed Matter::Materials Science, Quality (physics), 0103 physical sciences, Polariton, Optoelectronics, Mode switching, Photonics, 010306 general physics, 0210 nano-technology, business, Order of magnitude
Abstract

International audience; We report exciton-polariton condensation in a new family of fully hybrid ZnO based microcavity demonstrating the best-quality ZnO material available (a bulk substrate), a large quality factor (~4000) and large Rabi splittings (~240 meV). Condensation is achieved between 4 and 300 K and for excitonic fractions ranging between 17% and 96 %, which corresponds to a tuning of the exciton-polariton mass, lifetime and interaction constant by one order of magnitude. We demonstrate mode switching between polariton branches allowing, just by controlling the pumping power, to tune the photonic fraction by a factor 4.

Published
2013

25. LO-phonon-assisted polariton lasing in a ZnO-based microcavity

Author

Christelle Brimont, Laurent Orosz, Jesús Zúñiga-Pérez, Thierry Guillet, F. Médard, Fabrice Semond, Xavier Lafosse, Joël Leymarie, Guillaume Malpuech, Pierre Disseix, Mathieu Leroux, Sophie Bouchoule, Dimitri Solnyshkov, François Réveret, M. Mihailovic, Meletios Mexis, Laboratoire des sciences et matériaux pour l'électronique et d'automatique (LASMEA), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Centre National de la Recherche Scientifique (CNRS), Centre de recherche sur l'hétéroepitaxie et ses applications (CRHEA), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), Laboratoire de photonique et de nanostructures (LPN), Centre National de la Recherche Scientifique (CNRS), Laboratoire Charles Coulomb (L2C), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), ANR-06-BLAN-0135,ZOOM,Zinc Oxide Optical Microcavities(2006), European Project: 235114,EC:FP7:PEOPLE,FP7-PEOPLE-ITN-2008,CLERMONT4(2009), and Université Nice Sophia Antipolis (1965 - 2019) (UNS)

Subjects
Phonon, Exciton, FOS: Physical sciences, Physics::Optics, 02 engineering and technology, 01 natural sciences, Resonance (particle physics), Semiconductor laser theory, Condensed Matter::Materials Science, 0103 physical sciences, Polariton, 010306 general physics, Physics, Condensed Matter::Quantum Gases, Condensed Matter - Materials Science, Condensed matter physics, Scattering, Condensed Matter::Other, Materials Science (cond-mat.mtrl-sci), 021001 nanoscience & nanotechnology, Condensed Matter Physics, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, Electronic, Optical and Magnetic Materials, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], Relaxation (physics), 0210 nano-technology, Lasing threshold
Abstract

International audience; Polariton relaxation mechanisms are analyzed experimentally and theoretically in a ZnO-based polariton laser. A minimum lasing threshold is obtained when the energy difference between the exciton reservoir and the bottom of the lower polariton branch is resonant with the LO phonon energy. Tuning off this resonance increases the threshold, and exciton-exciton scattering processes become involved in the polariton relaxation. These observations are qualitatively reproduced by simulations based on the numerical solution of the semiclassical Boltzmann equations.

Published
2012

26. High quality factor photonic resonators for nitride quantum dots

Author

Meletios Mexis, Bernard Gil, Bruno Gayral, Thierry Guillet, Sylvain Sergent, Diane Sam-Giao, Stephanie Rennesson, Delphine Néel, Thierry Bretagnon, Mathieu Leroux, Christelle Brimont, Philippe Boucaud, Sylvain David, Fabrice Semond, Xavier Checoury, Laboratoire Charles Coulomb (L2C), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Centre de recherche sur l'hétéroepitaxie et ses applications (CRHEA), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), Institut d'électronique fondamentale (IEF), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Nanophysique et Semiconducteurs (NPSC), PHotonique, ELectronique et Ingénierie QuantiqueS (PHELIQS), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), ANR-08-NANO-0021,SINPHONI,Nanophotonique à base de nitrures intégrée sur silicium(2008), and Université Nice Sophia Antipolis (1965 - 2019) (UNS)

Subjects
010302 applied physics, Materials science, business.industry, 02 engineering and technology, Nitride, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, Waveguide (optics), Spectral line, Electronic, Optical and Magnetic Materials, Resonator, Optics, Quality (physics), Quantum dot, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], 0103 physical sciences, Optoelectronics, Photonics, 0210 nano-technology, business, Photonic crystal
Abstract

Phone: þ00 33 4 67 14 37 89, Fax: 00 33 4 67 14 37 60We report the realization and the optical study of nitridephotonic resonators dedicated to the blue and UV spectralrange. Microdisks and photonic crystal (PC) cavities areinvestigated containing GaN/AlN quantum dots (QDs)embedded in an AlN waveguide. The PC cavities are fabricatedthrough the conformal growth of nitrides on a patterned Sisubstrate,and presentdelocalized and confinedcavity modesintheir microphotoluminescence spectra, that are compared tosimulations. A large quality factor of 1800 is reached for amodified L3 cavity. In the case of microdisks, which arefabricated through a classical top-down approach, the series ofwhispering gallery modes (WGMs) with large quality factors(up to 7300) are observed and analysed.

Published
2012

27. Polariton lasing in a hybrid bulk ZnO microcavity

Author

Georg Rossbach, Bernard Gil, Jesús Zúñiga-Pérez, Laurent Orosz, Raphaël Butté, Thierry Bretagnon, François Réveret, Fabrice Semond, Meletios Mexis, Nicolas Grandjean, Thierry Guillet, Joël Leymarie, Mathieu Leroux, Sophie Bouchoule, Jacques Levrat, Christelle Brimont, Laboratoire Charles Coulomb (L2C), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Institute of Condensed Matter Physics [Lausanne], Ecole Polytechnique Fédérale de Lausanne (EPFL), Laboratoire des sciences et matériaux pour l'électronique et d'automatique (LASMEA), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Centre National de la Recherche Scientifique (CNRS), Centre de recherche sur l'hétéroepitaxie et ses applications (CRHEA), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), Laboratoire de photonique et de nanostructures (LPN), Centre National de la Recherche Scientifique (CNRS), ANR-06-BLAN-0135,ZOOM,Zinc Oxide Optical Microcavities(2006), European Project: 235114,EC:FP7:PEOPLE,FP7-PEOPLE-ITN-2008,CLERMONT4(2009), and Université Nice Sophia Antipolis (1965 - 2019) (UNS)

Subjects
Photon, Physics and Astronomy (miscellaneous), stimulated emission, Physics::Optics, 02 engineering and technology, semiconductor lasers, 01 natural sciences, Semiconductor laser theory, localised modes, Optical pumping, 0103 physical sciences, Zinc oxide, strong coupling, Polariton, Stimulated emission, light coherence, 010306 general physics, optical pumping, Physics, Condensed Matter::Quantum Gases, Condensed matter physics, wide band gap semiconductors, business.industry, Bose-Einstein Condensation, Condensed Matter::Other, nonlinear optics, Nonlinear optics, II-VI semiconductors, 021001 nanoscience & nanotechnology, microcavities, microcavity, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], microcavity lasers, polariton laser, Photonics, 0210 nano-technology, business, Lasing threshold, zinc compounds, polaritons
Abstract

We demonstrate polariton lasing in a bulk ZnO planar microcavity under non-resonant optical pumping at a small negative detuning (delta similar to -1/6 the 130 meV vacuum Rabi splitting) and a temperature of 120 K. The strong coupling regime is maintained at lasing threshold since the coherent nonlinear emission from the lower polariton branch occurs at zero in-plane wavevector well below the uncoupled cavity mode. The contribution of multiple localized polariton modes above threshold and the non-thermal polariton statistics show that the system is in a far-from-equilibrium regime, likely related to the moderate photon lifetime and in-plane photonic disorder in the cavity. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3650268]

Published
2011

28. Exciton radiative properties in nonpolar homoepitaxial ZnO/(Zn,Mg)O quantum wells

Author

Thierry Bretagnon, Christelle Brimont, Alexey Kavokin, Luc Beaur, Bernard Gil, M. Teisseire, Thierry Guillet, Dimitri Tainoff, Jean-Michel Chauveau, Laboratoire Charles Coulomb (L2C), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Centre de recherche sur l'hétéroepitaxie et ses applications (CRHEA), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), and ANR-06-NEUR-0042,PpP-AD,APPROCHE PSYCHOPHYSIQUE INTEGREE DE LA DISSOCIATION PERCEPTION-ACTION(2006)

Subjects
Condensed Matter::Quantum Gases, 010302 applied physics, Photoluminescence, Materials science, Condensed matter physics, Condensed Matter::Other, Exciton, 02 engineering and technology, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, Spectral line, Electronic, Optical and Magnetic Materials, Condensed Matter::Materials Science, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], Phase space, 0103 physical sciences, Radiative transfer, Spontaneous emission, 0210 nano-technology, Intensity (heat transfer), Quantum well
Abstract

International audience; Photoluminescence spectra of nonpolar M-plane ZnO/Zn0.8Mg0.2O quantum wells exhibit strong excitonic peaks from low (10 K) to high (325 K) temperatures. We find that the total integrated intensity remains quasiconstant and that the exciton lifetime increases linearly with the temperature from a value of 750 ps at 100 K until about 2.4 ns at 325 K. This behavior is well described by an original model accounting for the exciton phase space filling. This indicates that radiative recombination of free excitons is dominating the quantum well photoluminescence even at room temperature.

Published
2011

29. Laser emission with excitonic gain in a ZnO planar microcavity

Author

Bernard Gil, F. Médard, Jesús Zúñiga-Pérez, Pierre Valvin, Fabrice Semond, M. Mihailovic, Thierry Bretagnon, Mathieu Leroux, Thierry Guillet, Sophie Bouchoule, Christelle Brimont, Laboratoire Charles Coulomb (L2C), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Laboratoire des sciences et matériaux pour l'électronique et d'automatique (LASMEA), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Centre National de la Recherche Scientifique (CNRS), Centre de recherche sur l'hétéroepitaxie et ses applications (CRHEA), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), Laboratoire de photonique et de nanostructures (LPN), Centre National de la Recherche Scientifique (CNRS), ANR-06-BLAN-0135,ZOOM,Zinc Oxide Optical Microcavities(2006), European Project: 235114,EC:FP7:PEOPLE,FP7-PEOPLE-ITN-2008,CLERMONT4(2009), and Université Nice Sophia Antipolis (1965 - 2019) (UNS)

Subjects
Materials science, Physics and Astronomy (miscellaneous), Exciton, FOS: Physical sciences, Physics::Optics, 02 engineering and technology, 01 natural sciences, VCSEL, law.invention, Vertical-cavity surface-emitting laser, Semiconductor laser theory, Optical pumping, Condensed Matter::Materials Science, law, 0103 physical sciences, Zinc oxide, strong coupling, Polariton, 010306 general physics, Condensed Matter::Quantum Gases, business.industry, Scattering, Condensed Matter::Other, 021001 nanoscience & nanotechnology, Laser, Condensed Matter - Other Condensed Matter, microcavity, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], Optoelectronics, 0210 nano-technology, business, Lasing threshold, Optics (physics.optics), Other Condensed Matter (cond-mat.other), Physics - Optics
Abstract

International audience; The lasing operation of a ZnO planar microcavity under optical pumping is demonstrated from T=80 K to 300 K. At the laser threshold, the cavity switches from the strong coupling to the weak coupling regime. A gain-related transition, which appears while still observing polariton branches and, thus, with stable excitons, is observed below 240K. This shows that exciton scattering processes, typical of II-VI semiconductors, are involved in the gain process.

Published
2011

30. Low temperature reflectivity study of ZnO/(Zn,Mg)O quantum wells grown on M-plane ZnO substrates

Author

Bernard Gil, Luc Beaur, Thierry Bretagnon, Thierry Guillet, Dimitri Tainoff, M. Teisseire, Jean-Michel Chauveau, Christelle Brimont, Laboratoire Charles Coulomb (L2C), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Centre de recherche sur l'hétéroepitaxie et ses applications (CRHEA), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), and ANR-06-BLAN-0135,ZOOM,Zinc Oxide Optical Microcavities(2006)

Subjects
Materials science, Physics and Astronomy (miscellaneous), Exciton, FOS: Physical sciences, 02 engineering and technology, 01 natural sciences, Molecular physics, Condensed Matter::Materials Science, Quality (physics), 0103 physical sciences, Anisotropy, Quantum well, 010302 applied physics, Condensed Matter - Materials Science, Plane (geometry), Orthogonal polarization spectral imaging, Condensed Matter::Other, Wide-bandgap semiconductor, Materials Science (cond-mat.mtrl-sci), 021001 nanoscience & nanotechnology, 3. Good health, Condensed Matter - Other Condensed Matter, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], Quasiparticle, 0210 nano-technology, Other Condensed Matter (cond-mat.other)
Abstract

International audience; We report growth of high quality ZnO/Zn0.8Mg0.2O quantum well on M-plane oriented ZnO substrates. The optical properties of these quantum wells are studied by using reflectance spectroscopy. The optical spectra reveal strong in-plane optical anisotropies, as predicted by group theory, and marked reflectance structures, as an evidence of good interface morphologies. Signatures ofc onfined excitons built from the spin-orbit split-off valence band, the analog of exciton C in bulk ZnO are detected in normal incidence reflectivity experiments using a photon polarized along the c axis of the wurtzite lattice. Experiments performed in the context of an orthogonal photon polarization, at 90° of this axis, reveal confined states analogs of A and B bulk excitons. Envelope function calculations which include excitonic interaction nicely account for the experimental report.

Published
2011

31. AlN photonic crystal nanocavities realized by epitaxial conformal growth on nanopatterned silicon substrate

Author

Thierry Guillet, Christelle Brimont, Sylvain Sergent, Xavier Checoury, Sylvain David, Diane Sam-Giao, Thierry Bretagnon, Fabrice Semond, Bruno Gayral, Delphine Néel, Meletios Mexis, Philippe Boucaud, Institut d'électronique fondamentale (IEF), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Centre de recherche sur l'hétéroepitaxie et ses applications (CRHEA), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), Laboratoire Charles Coulomb (L2C), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Nanophysique et Semiconducteurs (NPSC), PHotonique, ELectronique et Ingénierie QuantiqueS (PHELIQS), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), and Université Nice Sophia Antipolis (1965 - 2019) (UNS)

Subjects
010302 applied physics, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], Materials science, Physics and Astronomy (miscellaneous), Silicon, business.industry, Hybrid silicon laser, chemistry.chemical_element, 02 engineering and technology, Substrate (electronics), 021001 nanoscience & nanotechnology, Epitaxy, 01 natural sciences, chemistry, Etching (microfabrication), 0103 physical sciences, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Optoelectronics, 0210 nano-technology, business, Layer (electronics), Photonic crystal, Molecular beam epitaxy
Abstract

International audience; An original method to fabricate III-nitride photonic crystal membranes without etching of III-N materials is reported. A photonic crystal pattern is first realized in a silicon substrate. GaN quantum dots embedded in a thin AlN layer are then grown by conformal epitaxy using ammonia-based molecular beam epitaxy on the top of the patterned silicon substrate and a free-standing membrane is achieved by selective etching of the silicon substrate through the holes of the photonic crystal. Room temperature microphotoluminescence measurements show a quality factor as high as 1800 at 425 nm on a modified L3 cavity. Possibility to achieve lasing with this system is discussed.

Published
2011

32. Correlation of structural properties with energy transfer of Eu-doped ZnO thin films prepared by sol-gel process and magnetron reactive sputtering

Author

A. Slaoui, Guy Schmerber, Julien Petersen, Aziz Dinia, Christelle Brimont, Mathieu Gallart, Claude Becker, Pierre Gilliot, Silviu Colis, Jean-Luc Rehspringer, Corinne Ulhaq-Bouillet, Groupe d'étude des semiconducteurs (GES), and Centre National de la Recherche Scientifique (CNRS)-Université Montpellier 2 - Sciences et Techniques (UM2)

Subjects
IONS, Photoluminescence, Materials science, Photoemission spectroscopy, Analytical chemistry, General Physics and Astronomy, Nanoparticle, chemistry.chemical_element, LUMINESCENCE PROPERTIES, 02 engineering and technology, 01 natural sciences, 7. Clean energy, Sputtering, 0103 physical sciences, NANOPARTICLES, Thin film, ZINC-OXIDE, Sol-gel, 010302 applied physics, OPTICAL-PROPERTIES, 021001 nanoscience & nanotechnology, Structural, Mechanical, Thermodynamic, and Optical Properties of Condensed Matter, GAN, PHOSPHORS, NANOCRYSTALS, chemistry, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], PHOTOLUMINESCENCE, Crystallite, 0210 nano-technology, Europium, EMISSION
Abstract

We investigated the structural and optical properties of Eu-doped ZnO thin films made by sol-gel technique and magnetron reactive sputtering on Si (100) substrate. The films elaborated by sol-gel process are polycrystalline while the films made by sputtering show a strongly textured growth along the c-axis. X-ray diffraction patterns and transmission electron microscopy analysis show that all samples are free of spurious phases. The presence of Eu2+ and Eu3+ into the ZnO matrix has been confirmed by x-ray photoemission spectroscopy. This means that a small fraction of Europium substitutes Zn2+ as Eu2+ into the ZnO matrix; the rest of Eu being in the trivalent state. This is probably due to the formation of Eu2O3 oxide at the surface of ZnO particles. This is at the origin of the strong photoluminescence band observed at 2 eV, which is characteristic of the D-5(0)-> F-7(2) Eu3+ transition. In addition the photoluminescence excitonic spectra showed efficient energy transfer from the ZnO matrix to the Eu3+ ion, which is qualitatively similar for both films although the sputtered films have a better structural quality compared to the sol-gel process grown films. (C) 2010 American Institute of Physics. [doi : 10.1063/1.3436628]

Published
2010

33. Relaxation and emission of Bragg-mode and cavity-mode polaritons in a ZnO microcavity at room temperature

Author

Pierre Disseix, J. C. Moreno, Stéphane Faure, Jesús Zúñiga-Pérez, Mathieu Leroux, Sophie Bouchoule, Thierry Guillet, Thierry Bretagnon, Fabrice Semond, Bernard Gil, Eric Frayssinet, F. Médard, Joël Leymarie, Delphine Lagarde, Christelle Brimont, Groupe d'étude des semiconducteurs (GES), Centre National de la Recherche Scientifique (CNRS)-Université Montpellier 2 - Sciences et Techniques (UM2), Laboratoire des sciences et matériaux pour l'électronique et d'automatique (LASMEA), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Centre National de la Recherche Scientifique (CNRS), Centre de recherche sur l'hétéroepitaxie et ses applications (CRHEA), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), Laboratoire de photonique et de nanostructures (LPN), Centre National de la Recherche Scientifique (CNRS), ANR-06-BLAN-0135,ZOOM,Zinc Oxide Optical Microcavities(2006), Université Montpellier 2 - Sciences et Techniques (UM2)-Centre National de la Recherche Scientifique (CNRS), and Université Nice Sophia Antipolis (1965 - 2019) (UNS)

Subjects
Materials science, Photoluminescence, Physics and Astronomy (miscellaneous), Exciton, FOS: Physical sciences, Physics::Optics, 02 engineering and technology, 01 natural sciences, 7. Clean energy, Condensed Matter::Materials Science, 0103 physical sciences, strong coupling, Polariton, 010306 general physics, Condensed Matter::Quantum Gases, Condensed matter physics, Condensed Matter::Other, Mode (statistics), 021001 nanoscience & nanotechnology, Reflectivity, Condensed Matter - Other Condensed Matter, microcavity, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], Strong coupling, Relaxation (physics), oxide, PACS: 71.35.-y, 71.36.+c, 78.20.-e, 78.55.Et, 0210 nano-technology, Excitation, Other Condensed Matter (cond-mat.other)
Abstract

International audience; The strong coupling regime in a ZnO microcavity is investigated through room temperature photoluminescence and reflectivity experiments. The simultaneous strong coupling of excitons to the cavity mode and the first Bragg mode is demonstrated at room temperature. The polariton relaxation is followed as a function of the excitation density. A relaxation bottleneck is evidenced in the Bragg-mode polariton branch. It is partly broken under strong excitation density, so that the emission from this branch dominates the one from cavity-mode polaritons.

Published
2009

34. Dislocation density and band structure effects on spin dynamics in GaN

Author

Atef Gadalla, Pierre Gilliot, Olivier Crégut, Christelle Brimont, Bernd Hönerlage, Mathieu Gallart, Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-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)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, and 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)

Subjects
Materials science, III-V semiconductors, Exciton, dislocation density, General Physics and Astronomy, RELAXATION, 02 engineering and technology, spin dynamics, FILMS, 01 natural sciences, Condensed Matter::Materials Science, 0103 physical sciences, reflectivity, SCATTERING, 010306 general physics, Electronic band structure, Wurtzite crystal structure, Condensed matter physics, wide band gap semiconductors, Scattering, EXCITONS, valence bands, Wide-bandgap semiconductor, semiconductor epitaxial layers, 021001 nanoscience & nanotechnology, Polarization (waves), OSCILLATOR-STRENGTHS, ELECTRONS, CHEMICAL-VAPOR-DEPOSITION, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], Relaxation (physics), Dislocation, gallium compounds, 0210 nano-technology, silicon compounds, SAPPHIRE
Abstract

We present experimental results obtained on wurtzite epitaxial GaN layers grown on sapphire and SiC substrates. Thanks to a set of samples with different values of the residual strain, we demonstrate that the high dislocation density enhances the spin relaxation rate through the Elliott-Yafet mechanism. This fact is validated by the T-1 temperature dependence of the spin-relaxation times. The influence of the valence-band structure on the hole-spin relaxation is also highlighted. In particular, a decrease in the hole-spin relaxation rate, accompanied by a strong polarization rate (similar to 50%) of the differential reflectivity signal (Delta R/R), is observed when the splitting Delta E-AB between the heavy-hole and the light-hole bands is larger than the broadening Gamma(A) of the A excitonic transition. On the contrary, the overlap of the A and B resonances for Gamma(A)>Delta E-AB is responsible for a decrease in the Delta R/R polarization rate (similar to 10%) and an enhancement of the spin relaxation rate.

Published
2009

35. Optical and spin coherence of excitons in zinc-blende GaN

Author

H. Mariette, S. Founta, Pierre Gilliot, Olivier Crégut, Thierry Amand, Delphine Lagarde, Xavier Marie, Andrea Balocchi, B. Hönerlage, Mathieu Gallart, Christelle Brimont, Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-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), Optoélectronique Quantique (LPCNO), Laboratoire de physique et chimie des nano-objets (LPCNO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-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-Institut de Chimie du CNRS (INC)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), 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)-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)-Centre National de la Recherche Scientifique (CNRS), Nanophysique et Semiconducteurs (NPSC), Institut Néel (NEEL), 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)-Université Joseph Fourier - Grenoble 1 (UJF), Université de Strasbourg (UNISTRA)-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)-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)-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 (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)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Nanophysique et Semiconducteurs (NEEL - NPSC), and 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)

Subjects
Photoluminescence, III-V semiconductors, excitons, Exciton, Dephasing, General Physics and Astronomy, time resolved spectra, RELAXATION, 02 engineering and technology, Electron, 01 natural sciences, 7. Clean energy, SEMICONDUCTORS, Condensed Matter::Materials Science, 0103 physical sciences, reflectivity, NITRIDE, 010306 general physics, Spectroscopy, Biexciton, Physics, electron spin polarisation, Condensed matter physics, wide band gap semiconductors, Condensed Matter::Other, Exchange interaction, exchange interactions (electron), semiconductor epitaxial layers, 021001 nanoscience & nanotechnology, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, 3. Good health, ELECTRONS, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], electron-hole recombination, photoluminescence, Time-resolved spectroscopy, gallium compounds, 0210 nano-technology
Abstract

The carrier recombination processes and the relaxation dynamics of spin-polarized excitons in cubic epitaxial GaN have been investigated by time-resolved photoluminescence and pump-probe spectroscopy experiments. We evidence a very fast exciton spin relaxation tau(S)similar to 0.3 ps that is influenced by both the high defect concentration and the strong electron-hole exchange interaction. Spectral oscillatory features of the transient reflectivity are observed for negative delays that allow us to determine the exciton optical dephasing time T-2.

Published
2009

36. Relaxation of electron-hole pairs by coherent emission of LO-phonons in the quantum kinetic regime measured in CdZnTe quantum wells

Author

Olivier Crégut, Mathieu Gallart, Pierre Gilliot, Christelle Brimont, S. Cronenberger, Henri Mariette, B. Hönerlage, Kuntheak Kheng, Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-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)-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), Laboratoire de Spectrométrie Physique (LSP), and Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Phonon, Exciton, Quantum point contact, SEMICONDUCTOR, 02 engineering and technology, 01 natural sciences, Condensed Matter::Materials Science, 0103 physical sciences, SCATTERING, 010306 general physics, Quantum, Quantum well, Physics, DOTS, Oscillation, EXCITONS, GAAS, MEMORY, Relaxation (NMR), Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Electronic, Optical and Magnetic Materials, MODEL, Quantum dot, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Condensed Matter::Strongly Correlated Electrons, Atomic physics, 0210 nano-technology
Abstract

We study the relaxation of excitons in CdZnTe quantum wells by emission of a LO-phonon cascade, ending with a trapping-in quantum dots. The state filling of the dots is measured in two-color pump-probe experiments. The observed optical-phonon emission time is found to be smaller (130 fs) than the phonon oscillation period (165 fs), showing that the interaction occurs in a quantum kinetic regime. This is evidenced by measuring the buildup of the phonon replica of an initially photocreated electron-hole pair distribution on a subpicosecond time scale.

Published
2008

37. Structural and photoluminescence properties of ZnO thin films prepared by sol-gel process

Author

Cédric Leuvrey, Abdelilah Slaoui, Guy Schmerber, Christiane Becker, Mathieu Gallart, Pierre Gilliot, Julien Petersen, B. Hönerlage, Olivier Crégut, Aziz Dinia, H. Aubriet, Christelle Brimont, Corinne Ulhaq-Bouillet, Silviu Colis, David Ruch, Jean-Luc Rehspringer, Jung, Marie-Anne, Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-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)-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), Laboratoire de technologies industrielles (LTI), Centre de Recherche Public Henri-Tudor [Luxembourg] (CRP Henri-Tudor), Institut d'Electronique du Solide et des Systèmes (InESS), Centre National de la Recherche Scientifique (CNRS), and Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS)

Subjects
Materials science, Photoluminescence, ZINC-OXIDE FILMS, Absorption spectroscopy, Analytical chemistry, General Physics and Astronomy, 02 engineering and technology, EXCITON, 01 natural sciences, EPILAYERS, FERROMAGNETISM, Condensed Matter::Materials Science, X-ray photoelectron spectroscopy, 0103 physical sciences, Thin film, ComputingMilieux_MISCELLANEOUS, Wurtzite crystal structure, 010302 applied physics, Spin coating, OPTICAL-PROPERTIES, Magnetic semiconductor, 021001 nanoscience & nanotechnology, Absorption edge, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], GROWTH, MAGNETIC SEMICONDUCTORS, 0210 nano-technology
Abstract

The present study focuses on the structural and optical properties of ZnO thin films fabricated by sol-gel process and spin coated onto Si (100) and quartz substrates. The ZnO films have a hexagonal wurtzite structure with a grain size of about 50 nm. The x-ray photoelectron spectroscopy measurements reveal the presence of Zn2+ and of zinc hydroxyl groups at the film. Optical properties were studied by photoluminescence (PL) and absorption spectroscopy at low and room temperatures. The absorption spectrum is dominated by a sharp excitonic peak at room and low temperatures. At room temperature, PL observations show two transitions: one near the absorption edge in the ultraviolet (UV) region and the second centered at 640 nm, characteristic of the deep electronic levels in the bandgap. The spectrum at 6 K is dominated by donor bound exciton lines and donor-acceptor pair transitions. LO-phonon replica and two-electron satellite transitions are also observed. These optical characteristics are a signature of good structural quality of the films. c 2008 American Institute of Physics. [DOI: 10.1063/1.3021358]

Published
2008

38. Experimental investigation of excitonic spin relaxation dynamics in GaN

Author

B. Hönerlage, Christelle Brimont, Mathieu Gallart, Pierre Gilliot, Olivier Crégut, Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-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)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, and 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)

Subjects
QUANTUM-WELLS, Dephasing, Exciton, 02 engineering and technology, Electron, 01 natural sciences, SEMICONDUCTORS, Spectral line, Condensed Matter::Materials Science, 0103 physical sciences, 010306 general physics, Electronic band structure, Wurtzite crystal structure, Physics, SPECTROSCOPY, Spin polarization, Condensed matter physics, Relaxation (NMR), OPTICAL-PROPERTIES, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 3. Good health, Electronic, Optical and Magnetic Materials, ELECTRONS, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], 0210 nano-technology
Abstract

By performing nondegenerate pump-probe experiments, we study the relaxation dynamics of spin-polarized A and B excitons in wurtzite epitaxial GaN. By analyzing the differential reflectivity spectra $(\ensuremath{\Delta}R∕R)$ of the two circularly polarized probe components, we are able to identify each spin relaxation channel (electron, light- and heavy-hole spin flips) separately and to extract characteristic times of the different spin relaxation processes. In addition, spectral oscillatory features are observed for negative delays. They show a rapid rise determined by the fast dephasing time ${T}_{2}$ of the excitonic transitions. We show that the high density of dislocations increases the spin relaxation of electrons and holes through the Elliot--Yafet mechanism and makes the exciton dephasing time very short. The measured heavy-hole relaxation time, which is not extremely short compared to the electron relaxation time, can be related to the band structure, in which the degeneracy between different spin valence bands is partially lifted.

Published
2008

39. Exciton-spin dephasing and relaxation due to symmetry breaking in two-band bulk semiconductors

Author

B. Hönerlage, Steeve Cronenberger, Christelle Brimont, Mathieu Gallart, Pierre Gilliot, Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-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)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, and 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)

Subjects
Physics, DYNAMICS, POLARITONS, Spin states, Condensed matter physics, Spin polarization, QUANTUM-WELLS, Exciton, Dephasing, Spontaneous symmetry breaking, 02 engineering and technology, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, Electronic, Optical and Magnetic Materials, ELECTRONS, Explicit symmetry breaking, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], 0103 physical sciences, Spin-flip, Symmetry breaking, 010306 general physics, 0210 nano-technology
Abstract

The full point group symmetry of a crystal can be broken due to internal or external effective fields. In the study of excitons, such symmetry breaking can lead to a coupling of different exciton states and if a system is prepared in an exciton state with a defined total angular momentum (pseudospin), spin beating is obtained. Looking at the fluctuations of these fields, we use the invariant expansion of an effective Hamiltonian to investigate exciton-spin-relaxation dynamics in a model two-band bulk semiconductor and discuss the respective importance of the different spin-flip processes. We find that interaction terms leading to an electron or hole spin flip give rise to a pure transverse dephasing. Terms where the electron and hole spins are simultaneously reversed lead to transitions between the spin states, which are characterized by the longitudinal relaxation time. Similar to motional narrowing in the case of free carriers, the latter process can lead to an increase in the exciton-spin-relaxation times if extrinsic electric, magnetic, or strain fields rapidly fluctuate in the sample. This effect is shown to be due to the electron-hole exchange interaction.

Published
2008

40. Excitonic spin relaxation in GaN

Author

B. Hönerlage, Olivier Crégut, Christelle Brimont, Mathieu Gallart, Pierre Gilliot, Groupe d'étude des semiconducteurs (GES), Centre National de la Recherche Scientifique (CNRS)-Université Montpellier 2 - Sciences et Techniques (UM2), Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-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)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, and 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)

Subjects
DYNAMICS, QUANTUM-WELLS, Exciton, General Physics and Astronomy, Light hole, 02 engineering and technology, Electron, Epitaxy, 01 natural sciences, Condensed Matter::Materials Science, 0103 physical sciences, 010306 general physics, Electronic band structure, Spin relaxation, Wurtzite crystal structure, Physics, Valence (chemistry), Spin polarization, Condensed matter physics, Chemistry, Relaxation (NMR), GAAS, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 3. Good health, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], 0210 nano-technology
Abstract

By performing non-degenerate pump-probe experiments, we study the relaxation dynamics of spin-polarized A and B excitons in wurtzite epitaxial GaN. By analyzing the differential reflection of the two circularly polarized probe components, we extract characteristic times of the different spin relaxation processes. We show that the spin relaxation of the exciton as a whole is negligible in regard to the spin relaxation of the individual carriers. We determined Te = 15 ps for the electron in the conduction band, Thh = 5 ps, and Tlh = 1.5 ps for the heavy hole and for the light hole, respectively. The quite long HH relaxation time can be related to the band structure in which the degeneracy between different spin valence bands is lifted. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Published
2007

41. Measurement of exciton spin coherence by nondegenerate four-wave mixing experiments in the chi((3)) regime

Author

Olivier Crégut, Pierre Gilliot, B. Hönerlage, S. Cronenberger, H. Rahimpour Soleimani, Mathieu Gallart, Christelle Brimont, Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), and Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS)

Subjects
POLARITONS, DYNAMICS, Coherence time, Spin states, QUANTUM-WELLS, RELAXATION, 02 engineering and technology, 01 natural sciences, SEMICONDUCTORS, symbols.namesake, Four-wave mixing, CUCL, 0103 physical sciences, Faraday effect, ABSORPTION, 010306 general physics, Biexciton, Physics, Condensed Matter::Quantum Gases, Condensed matter physics, Spin polarization, Condensed Matter::Other, 021001 nanoscience & nanotechnology, Condensed Matter Physics, BIEXCITONS, Electronic, Optical and Magnetic Materials, Magnetic field, LIGHT, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], symbols, Condensed Matter::Strongly Correlated Electrons, ORIENTATION, 0210 nano-technology, Coherence (physics)
Abstract

We demonstrate that the spin coherence relaxation of excitons can be measured in a three-beam four-wave mixing experiment in the chi((3)) regime, using a sequence of contracircularly polarized pulses. In contrast to other techniques like Faraday rotation measurement, our method allows one to access spin coherence without applying an external magnetic field. The superposition of opposite spin states (exciton-polariton spin coherence) is then probed in a nondegenerate configuration at the biexciton-exciton transition. Measurements are performed on a bulk CuCl platelet. The polariton effect is taken into account by modeling the propagation of the pulses. The exciton-polariton spin coherence time is demonstrated to be mainly determined by their spin lifetime.

Published
2007

42. Dislocation-enhanced spin relaxation in wurtzite GaN

Author

B. Hönerlage, Christelle Brimont, Olivier Crégut, Pierre Gilliot, Mathieu Gallart, Groupe d'étude des semiconducteurs (GES), Université Montpellier 2 - Sciences et Techniques (UM2)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-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)-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), and Aigle, Ges

Subjects
QUANTUM-WELLS, Biophysics, Gallium nitride, 02 engineering and technology, Spin dynamics, Nitride, Epitaxy, 01 natural sciences, Biochemistry, Condensed Matter::Materials Science, chemistry.chemical_compound, [PHYS.COND.CM-GEN] Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], 0103 physical sciences, Dislocation, Ultrafast process, 010306 general physics, Wurtzite crystal structure, Condensed matter physics, General Chemistry, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Crystallographic defect, Atomic and Molecular Physics, and Optics, ELECTRONS, 3. Good health, chemistry, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], Relaxation (physics), Spin-flip, 0210 nano-technology
Abstract

By performing non-degenerate pump-probe experiments, we study the relaxation dynamics of spin-polarized excitons in wurtzite epitaxial gallium nitride (GaN). Characteristic times of the different spin-relaxation channel (electron, heavy- and light- or split-off-hole spin flips) for different samples as a function of temperature are extracted. We show that the high dislocation density increases the spin relaxation of electrons and holes through the defect-assisted Elliot-Yafet mechanism. (C) 2009 Elsevier B.V. All rights reserved.

Published
2009

43. High quality factor AlN nanocavities embedded in a photonic crystal waveguide

Author

Fabrice Semond, Jean-Yves Duboz, Delphine Néel, M. J. Rashid, Sylvain David, Xavier Checoury, Diane Sam-Giao, Philippe Boucaud, Meletios Mexis, Bruno Gayral, Christelle Brimont, Thierry Guillet, Sylvain Sergent, Nanophysique et Semiconducteurs (NPSC), PHotonique, ELectronique et Ingénierie QuantiqueS (PHELIQS), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institut d'électronique fondamentale (IEF), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Centre de recherche sur l'hétéroepitaxie et ses applications (CRHEA), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), Laboratoire Charles Coulomb (L2C), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), European Project: 235114,EC:FP7:PEOPLE,FP7-PEOPLE-ITN-2008,CLERMONT4(2009), and Université Nice Sophia Antipolis (... - 2019) (UNS)

Subjects
Photoluminescence, Materials science, Physics and Astronomy (miscellaneous), Silicon, Physics::Instrumentation and Detectors, business.industry, Wide-bandgap semiconductor, Physics::Optics, chemistry.chemical_element, 02 engineering and technology, Substrate (electronics), 021001 nanoscience & nanotechnology, 01 natural sciences, 010309 optics, Condensed Matter::Materials Science, chemistry, Etching (microfabrication), Quantum dot, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], 0103 physical sciences, Optoelectronics, Reactive-ion etching, 0210 nano-technology, business, Photonic crystal
Abstract

International audience; We present a spectroscopic study of nanocavities obtained by small modifications of a W1 waveguide in an AlN photonic crystal membrane. The AlN film containing GaN quantum dots is grown on silicon. The photonic crystal structure is defined by e-beam lithography and etched by inductively coupled plasma reactive ion etching, while the membrane is released by selective etching of the silicon substrate. The room temperature photoluminescence of the embedded quantum dots reveals the existence of even-symmetry and odd-symmetry confined cavity modes and guided modes. Cavity mode quality factors up to 4400 at 395 nm and 2300 at 358 nm are obtained.

Published
2012

44. High quality factor nitride-based optical cavities: microdisks with embedded GaN/Al(Ga)N quantum dots

Author

Sylvain David, Delphine Néel, Meletios Mexis, Mathieu Leroux, Philippe Boucaud, Bernard Gil, Thierry Guillet, Christelle Brimont, Sylvain Sergent, Thierry Bretagnon, Xavier Checoury, Fabrice Semond, Laboratoire Charles Coulomb (L2C), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Centre de recherche sur l'hétéroepitaxie et ses applications (CRHEA), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), Institut d'électronique fondamentale (IEF), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), and ANR-08-NANO-0021,SINPHONI,Nanophotonique à base de nitrures intégrée sur silicium(2008)

Subjects
Materials science, Photoluminescence, Band gap, FOS: Physical sciences, 02 engineering and technology, Nitride, 01 natural sciences, Barrier layer, Optics, Etching (microfabrication), 0103 physical sciences, 010302 applied physics, Condensed Matter - Materials Science, business.industry, Materials Science (cond-mat.mtrl-sci), 021001 nanoscience & nanotechnology, Atomic and Molecular Physics, and Optics, Condensed Matter - Other Condensed Matter, Quantum dot, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], Q factor, Optoelectronics, Whispering-gallery wave, 0210 nano-technology, business, Other Condensed Matter (cond-mat.other)
Abstract

International audience; We compare the quality factor values of the whispery gallery modes of microdisks incorporating GaN quantum dots (QDs) grown on AlN and AlGaN barriers by performing room temperature photoluminescence (PL) spectroscopy. The PL measurements show a large number of high Q factor (Q) resonant modes on the whole spectrum which allows us to identify the different radial mode families and to compare them with simulations. We report a considerable improvement of the Q factor which reflect the etching quality and the relatively low cavity loss by inserting QDs into the cavity. GaN/AlN QDs based microdisks show very high Q values (Q > 7000) whereas the Q factor is only up to 2000 in microdisks embedding QDs grown on AlGaN barrier layer. We attribute this difference to the lower absorption below bandgap for AlN barrier layers at the energies of our experimental investigation.

Published
2011

45. LO-phonon cascade emission in CdZnTe quantum wells: coherent control and quantum kinetics

Author

H. Mariette, S. Cronenberger, Christelle Brimont, Pierre Gilliot, B. Hönerlage, Kuntheak Kheng, Olivier Crégut, Mathieu Gallart, Groupe d'étude des semiconducteurs (GES), and Centre National de la Recherche Scientifique (CNRS)-Université Montpellier 2 - Sciences et Techniques (UM2)

Subjects
Physics, History, Photon, Phonon, 7. Clean energy, 01 natural sciences, 010305 fluids & plasmas, Computer Science Applications, Education, Quantum dot, Coherent control, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], Picosecond, Excited state, 0103 physical sciences, Emission spectrum, Atomic physics, 010306 general physics, Quantum well
Abstract

We study in CdZnTe quantum wells (QW) the quantum kinetics of the LO-phonon cascade which is emitted by photo-excited electron-holes pairs. We perform time-resolved photoluminescence (PL) and pump-and-probe (P&P) experiments where we take advantage of the electron-hole pair trapping in quantum dots (QDs), which imprints a spectral signature of the LO-phonon cascade in the inhomogeneously broadened QD absorption and emission lines. Using first spectrally narrow picosecond exciting pulses, we determine, from the rise time of the P&P or PL signals, the LO-phonon emission time tau(LO) = 130 fs. This measurement shows that the process has to be described in the framework of quantum kinetics. The value tau(LO) is, indeed, shorter than the phonon oscillation period which is T-LO = 2(pi/omega LO) = 165 fs. It means that the energy conservation rule which is used in rate equations is relaxed. Memory effects are evidenced by the build up of the signal modulation. In a second set of experiments, we use a sequence of two femtosecond phase-locked pulses to achieve the coherent control of the phonon emission. The decaying coherence of the carrier-phonon system which is excited by the first pulse is probed by the second one: their interference results in a spectral channeled spectrum of the electron-hole pairs populations excited in the QW, which is replicated at lower photon energies in the QD P&P spectrum. We thus measure the coherence decay of the electron-hole pairs coupled to LO-phonons. We find that it is close to their lifetime.

Published
2007

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