Search

Political narrative is an instrument for political actors to construct a shared meaning, and it can be harnessed to harm political opponents. The Italian invaders, the Ethiopian Student Movement, the Tigray People’s Liberation Front, the Oromo Liberation Front, and the incumbent regime contributed in varying degrees to the Amhara domination narrative. TPLF, in its political manifesto and later in the 1995 FDRE constitution, institutionally crafted an anti-Amhara narrative, reaching a crescendo after Abiy Ahmed assumed office in 2018. Thus, this research article tried to scrutinise and weigh the discourse of institutionally crafted Amhara existential threats. The study employed a qualitative research tradition and an exploratory research design approach that involved a political-economic analysis. The study finds that the century-old Amhara domination narrative, coupled with institutionally supported recurrent mass killings and expulsion, especially in Oromia, Benishangul-Gumuz, and Amhara regional states, posed a real and perceived existential threat that gave birth to the Amhara Fano armed struggle. [ABSTRACT FROM AUTHOR]

Despite much attention to physical aspects of climate change, the relationship between climate change and culture has thus far received little attention in research. Cultures develop over time and are shaped by place-specific factors such as history, landscape, weather, flora and fauna. Climate change affects these contextual factors, and as such will have consequences for the cultures shaped by them. In addressing the intersection of culture and climate change, the paper draws on a qualitative study on Fanø, a low-lying Danish island in the Wadden Sea. We illustrate how the cultural heritage of Fanø's seafaring past plays an important role in the everyday culture of the present. The cultural heritage and the nature of Fanø are at the core of the island's identity. As climate change will affect the community's ability to maintain their cultural heritage and will change the island's natural values, it will affect what it means to be Fanniker. [ABSTRACT FROM AUTHOR]

Highly efficient Metamaterials are necessary for applications in sensing, communication, etc. Fano resonance and electromagnetically induced transparency-like phenomena are essential for obtaining high Q-factor and sensitive Metamaterials. Employing both numerical simulations and experimental analysis, we investigate the emergence of Fano resonance in cross-resonator Metamaterials facilitated by the conductive coupling between dark and bright resonators. We analyze the gradual shift of the fano resonance by tuning the dark resonator and finally form an electromagnetically induced transparency-like transmission peak. The strong coupling of the resonator is observed in the form of an anti-crossing and discussed through analytical models. We demonstrate that the coupling strength of the dark and bright resonance in our metamaterial is proportional to the asymmetry parameter, albeit at the cost of the Fano resonance's Q-factor. The findings and methods introduced in this study can be used to develop highly efficient THz Metamaterials for various applications operable in room conditions. [ABSTRACT FROM AUTHOR]

Let G be a semi-simple simply connected algebraic group over the field ℂ of complex numbers. Let T be a maximal torus of G, and let W be the Weyl group of G with respect to T. Let Z(w, i) be the Bott-Samelson-Demazure-Hansen variety corresponding to a tuple i associated to a reduced expression of an element w ∈ W. We prove that for the tuple i associated to any reduced expression of a minuscule Weyl group element w, the anti-canonical line bundle on Z(w, i) is globally generated. As consequence, we prove that Z(w, i) is weak Fano. Assume that G is a simple algebraic group whose type is different from A2. Let S = {α1, ..., αn} be the set of simple roots. Let w be such that support of w is equal to S. We prove that Z(w, i) is Fano for the tuple i associated to any reduced expression of w if and only if w is a Coxeter element and w − 1 (∑ t = 1 n α t) ∈ − S . [ABSTRACT FROM AUTHOR]

Abstract Highly efficient Metamaterials are necessary for applications in sensing, communication, etc. Fano resonance and electromagnetically induced transparency-like phenomena are essential for obtaining high Q-factor and sensitive Metamaterials. Employing both numerical simulations and experimental analysis, we investigate the emergence of Fano resonance in cross-resonator Metamaterials facilitated by the conductive coupling between dark and bright resonators. We analyze the gradual shift of the fano resonance by tuning the dark resonator and finally form an electromagnetically induced transparency-like transmission peak. The strong coupling of the resonator is observed in the form of an anti-crossing and discussed through analytical models. We demonstrate that the coupling strength of the dark and bright resonance in our metamaterial is proportional to the asymmetry parameter, albeit at the cost of the Fano resonance’s Q-factor. The findings and methods introduced in this study can be used to develop highly efficient THz Metamaterials for various applications operable in room conditions.

Monolayer two-dimensional transition metal dichalcogenide (TMD)-based materials have become one of the ideal platforms for the study of multibody interactions due to their rich excitonic complexes. The coupling between optical nanocavity and material has become an important means for manipulating the optical properties of materials, but there are few studies on the coupling of nanocavities and the multi-body effect in materials. In this study, we investigate the optical properties of silver nanodisk (Ag ND) arrays covering a monolayer WS2. In the experimental sample, we observed a ~114.3-fold photoluminescence enhancement of charged biexciton in the heterostructure region, as compared to the monolayer WS2 region, a value which is much higher than those for exciton (~2.2-fold) and trion (~16.4-fold), a finding which is attributed to the Fano resonant coupling between monolayer WS2 and the Ag ND. By means of time-resolved spectroscopy, we studied the carrier dynamics in the hybrid system. Our findings reveal that resonant coupling promotes the formation and radiation recombination processes of the charged biexciton, significantly reducing the radiative recombination lifetime by ~15-fold, which is much higher than the measurement in exciton (~2-fold). Our results provide an opportunity to understand the multibody physics of coupling with nanocavities, which could facilitate the application of multi-body excitons in the fields of light-emitting devices and lasers, etc. [ABSTRACT FROM AUTHOR]

We apply the Berglund–Hübsch transpose rule from BHK mirror symmetry to show that to an n - 1 -dimensional Calabi–Yau orbifold in weighted projective space defined by an invertible polynomial, we can associate four (possibly) distinct Sasaki manifolds of dimension 2 n + 1 which are n - 1 -connected and admit a metric of positive Ricci curvature. We apply this theorem to show that for a given K3 orbifold, there exist four seven-dimensional Sasakian manifolds of positive Ricci curvature, two of which are actually Sasaki–Einstein. [ABSTRACT FROM AUTHOR]

We show that a certain compactification X g of the SL 2 (C) free group character variety X (F g , SL 2 (C)) is Fano. This compactification has been studied previously by the second author, and separately by Biswas, Lawton, and Ramras. Part of the proof of this result involves the construction of a large family of integral reflexive polytopes. [ABSTRACT FROM AUTHOR]

Monolayer two-dimensional transition metal dichalcogenide (TMD)-based materials have become one of the ideal platforms for the study of multibody interactions due to their rich excitonic complexes. The coupling between optical nanocavity and material has become an important means for manipulating the optical properties of materials, but there are few studies on the coupling of nanocavities and the multi-body effect in materials. In this study, we investigate the optical properties of silver nanodisk (Ag ND) arrays covering a monolayer WS2. In the experimental sample, we observed a ~114.3-fold photoluminescence enhancement of charged biexciton in the heterostructure region, as compared to the monolayer WS2 region, a value which is much higher than those for exciton (~2.2-fold) and trion (~16.4-fold), a finding which is attributed to the Fano resonant coupling between monolayer WS2 and the Ag ND. By means of time-resolved spectroscopy, we studied the carrier dynamics in the hybrid system. Our findings reveal that resonant coupling promotes the formation and radiation recombination processes of the charged biexciton, significantly reducing the radiative recombination lifetime by ~15-fold, which is much higher than the measurement in exciton (~2-fold). Our results provide an opportunity to understand the multibody physics of coupling with nanocavities, which could facilitate the application of multi-body excitons in the fields of light-emitting devices and lasers, etc.

Anti-site disorder, arising due to the similar size of Fe and Mo ions in Sr2FeMoO6 (SFMO) double perovskites, hampers spintronic applicability by deteriorating the magnetic response of this double perovskite system. A higher degree of anti-site disorder can also completely destroy the half-metallicity of the SFMO system. To study the effects of different process gas conditions on the anti-site disorder, we have prepared a series of SFMO thin films on SrTiO3 (001) single-crystal substrate using a pulsed laser deposition (PLD) technique. The films are grown either under vacuum or under N2/O2 partial gas pressures. The vacuum-grown SFMO film shows the maximum value of saturation magnetization (MS) and Curie temperature (TC), signaling the lowest anti-site disorder in this series. In other words, there is a long-range Fe/Mo-O-Mo/Fe ferrimagnetic exchange in the vacuum-grown thin film, thereby enhancing the magnetization. Further, all the SFMO films show a semiconducting state with a systematic increase in overall resistivity with the increased anti-site disorder. The electrical conduction mechanism is defined by the variable-range hopping model at low temperatures. Raman spectra show a weak Fano peak, suggesting the presence of electron–phonon coupling in SFMO thin films. These results show the significance of the process gas in causing anti-site disorder, tuning the degree of this disorder and therefore its influence on the structural, magnetic, electrical, and vibrational properties of SFMO thin films. [ABSTRACT FROM AUTHOR]

A nanoantenna with Fano response is designed with plasmonic oligomers as a refractive index sensor to enhance surface-enhanced Raman scattering (SERS) in the visible light spectrum. The scattered radiation and field-enhanced interactions of the outer gallium phosphide (GaP) nanoring assembled with an inner heptamer of silver with Fano response are investigated systematically using the finite element method. The characteristics of Fano resonance are found to depend on the size, shape and nature of the materials in the hybrid nanoantenna. The confined electromagnetic field produces a single-point electromagnetic hotspot with up to 159.59 V/m. The sensitivity obtained from the wavelength shift and variation in the scattering cross-section (SCS) shows a maximum value of 550 nm/RIU. The results validate the design concept and demonstrate near-field enhancement, enabling the design of high-performance nanoantennas with enhanced optical sensing and SERS properties. [ABSTRACT FROM AUTHOR]

In this paper, a metal–insulator-metal (MIM) plasmonic absorber consisting of asymmetric double bars with bent arms located on top of a silica layer coated on a metal film is proposed, and its resonant features are analyzed. The suggested structure supports both Fano and dipole perfect absorption resonances at the near-infrared region (NIR). The asymmetry introduced into the structure can be induced by changing the bending angle or rotation angle of one of the antennas, while the other one remains fixed. Simulation results demonstrate that by applying both asymmetry factors to the structure, one can have two individual Fano peaks at the same time. It is shown that the magnitude, central wavelength, and line width of the Fano peaks are adjustable by controlling the geometrical parameters of the structure. It is also indicated that the quality factor (Q-factor) of the Fano resonance is inversely related to the degree of asymmetry introduced into the structure. According to the simulations, an ultra-narrow resonance peak with a bandwidth of 1.87 nm at the wavelength of 710 nm (corresponding to a Q-factor of 387) can be obtained by controlling the geometrical parameters. It is also discussed that the absorptivity of Fano and the dipole peaks can be adjusted inversely, by manipulating the grapheme chemical potential. The ratio of the absorptivity to the chemical potential of graphene about 275%/eV and 226%/eV is calculated for the Fano peak and dipole peak, respectively. Accordingly, the presented structure is an adjustable NIR absorber with a fully tunable absorption spectrum which can be utilized in various applications from tunable reflectors and photo-detectors to ultra-narrowband and broadband optical modulators. [ABSTRACT FROM AUTHOR]

Anti-site disorder, arising due to the similar size of Fe and Mo ions in Sr2FeMoO6 (SFMO) double perovskites, hampers spintronic applicability by deteriorating the magnetic response of this double perovskite system. A higher degree of anti-site disorder can also completely destroy the half-metallicity of the SFMO system. To study the effects of different process gas conditions on the anti-site disorder, we have prepared a series of SFMO thin films on SrTiO3 (001) single-crystal substrate using a pulsed laser deposition (PLD) technique. The films are grown either under vacuum or under N2/O2 partial gas pressures. The vacuum-grown SFMO film shows the maximum value of saturation magnetization (MS) and Curie temperature (TC), signaling the lowest anti-site disorder in this series. In other words, there is a long-range Fe/Mo-O-Mo/Fe ferrimagnetic exchange in the vacuum-grown thin film, thereby enhancing the magnetization. Further, all the SFMO films show a semiconducting state with a systematic increase in overall resistivity with the increased anti-site disorder. The electrical conduction mechanism is defined by the variable-range hopping model at low temperatures. Raman spectra show a weak Fano peak, suggesting the presence of electron–phonon coupling in SFMO thin films. These results show the significance of the process gas in causing anti-site disorder, tuning the degree of this disorder and therefore its influence on the structural, magnetic, electrical, and vibrational properties of SFMO thin films.

A historical meditation on non-Euclidean geometry, three Jesuits, a radical egalitarian mathematical philosopher, and the atom bomb, structured by word-count with attention to divisors of 441 and the Fano plane. [ABSTRACT FROM AUTHOR]

In this paper, a plasmonic metasurface is proposed and designed that has switching capability and it can be used as a quantum switch as well as an optical sensor. To provide the switching characteristic, Kerr material is used with dimer split ring resonator. The Kerr material is considered to change the response from Fano to Lorentzian shape, thus two logical values of 0 and 1 can be made at the Fano dip resonance. The Characteristic Mode Theory is investigated to predict the occurrence of the Fano response with exact wavelength. The study shows that Fano response appears when the phase of CMT modes is around 90°. As a result, the Kerr material can impact the phase of CMT modes, that makes switching characteristic for the proposed metasurface, by reducing the phase value to 40° for various Kerr material implementation in the metasurface. Also in this paper, using eigenvalues, the exact location of the Fano response, was obtained and bright and dark modes are detected without plotting characteristic currents. The proposed metasurface is developed for optical sensing with high sensitivity as a part of optical and quantum spectroscopy. The sensitivity of the sensor is obtained around 400 nm/RIU which is sufficient to distinguish the materials and to have high resolution. [ABSTRACT FROM AUTHOR]

We report a plasmon ruler based on an ultranarrow and near-symmetric cavity plasmon mode in dielectric–metal core–shell resonators (DMCSRs), demonstrating the ability to probe a sub-nanometer spectral shift and radius differential resolution. Specifically, the ultranarrow and near-symmetric cavity plasmon mode (TE1) is experimentally achieved via the opening engineering of a Ag shell, which is engineered only by incorporating nanometric uniform aluminum oxide layer (Al2O3, ∼5 to 15 nm) growth using atomic-layer deposition technology into a polystyrene microsphere core of DMCSRs. The TE1 cavity plasmon mode with an ultranarrow linewidth (∼12 nm) and a near-symmetric lineshape demonstrates excellent identification capabilities for probing a 0.23 nm spectral shift and a 0.75 nm radius spatial differential resolution in in situ thermal expansion experiments. Our findings offer an unprecedented opportunity for using the ultranarrow and symmetric cavity plasmons in ultrasensitive sensing applications. [ABSTRACT FROM AUTHOR]

Let G be a semi-simple simply connected algebraic group over an algebraically closed field k of arbitrary characteristic. Let B be a Borel subgroup of G containing a maximal torus T of G. Let W be the Weyl group of G with respect to T. For an arbitrary sequence w = (s i 1 , s i 2 , ... , s i r ) of simple reflections in W , let Z w be the Bott-Samelson-Demazure-Hansen variety (BSDH-variety for short) corresponding to w. Let Z w ˜ : = G × B Z w denote the fibre bundle on G / B whose fibre over B / B is Z w. In this article, we give necessary and sufficient conditions for the varieties Z w and Z w ˜ to be Fano (weak-Fano). We show that a line bundle on Z w is globally generated if and only if it is nef. We show that the Picard group Pic ( Z w ˜) is free abelian and we construct a O (1) -basis. We characterize the nef, globally generated, ample and very ample line bundles on Z w ˜ in terms of the O (1) -basis. [ABSTRACT FROM AUTHOR]

The phenomenon of extraordinary optical transmission (EOT) due to its advantages has been considered by researchers in various applications, and in recent years, many efforts have been made to engineer these structures to get the best possible response for desired applications. In this work, the optical properties of novel binary gold nanohole arrays are investigated theoretically. We engineered the optical response of the system by adjusting the ratio of contribution of surface plasmon polariton (SPP) to localized surface plasmon resonance (LSPR) through the manipulation of the geometrical properties. The changes in the topology of this nanohole array affected the intensity and the wavelength of transmission peaks. The sensitivity of the optical response to the refractive index was also investigated. The designed structure is a good candidate for use as a polarization-independent optical label-free sensor. [ABSTRACT FROM AUTHOR]

This brief proposes a hardware implementation architecture for Fano decoding of polarization-adjusted convolutional (PAC) codes. This architecture uses a novel branch metric unit specific to PAC codes. The proposed decoder is tested on FPGA, and its performance is evaluated on ASIC using TSMC 28 nm 0.72 V library. The decoder can be clocked at 500 MHz and reach an average information throughput of 38 Mb/s at 3.5 dB signal-to-noise ratio for a block length of 128 and a code rate of 1/2. [ABSTRACT FROM AUTHOR]

Copyright of Storia Urbana is the property of FrancoAngeli srl and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This article, based on modern and historical sources on this topic, describes the practical and scientific activities of representatives of "Indian mysticism" on religious tolerance. In this regard, it can be said with confidence that the attention given by the Sufis to national customs, traditions and even their language, regardless of the nationality and religion of Indian citizens, is a practical proof of our opinion. Because as a result of the activities of the aforementioned Sufis, the constant visits of the local population to the places of their choice were a vital reflection of the virtues of religious tolerance, the emergence of prosperous transitions. The study and mastery of local languages and religious sources, which are an integral part of Sufi scholarly activity, over time, began to find their own positive reflection among Indians. The study and mastery of local languages and religious sources, which are an integral part of Sufi scholarly activity, over time began to find their own positive reflection among Indians. Thus, this incident led to the emergence of a spirit of compassion instead of alienation between the representatives of Islam and Hinduism. Moreover, Sufi scholars focused on the commonality of Hinduism and Sufi teachings and, finally, on the cultural and educational cooperation of Indian and Muslim writers, not only spread and assimilated Islam in India, but Mahatma Gandhi also described: He also laid the foundation for the formation of the symbol of "one nation ". Thus, the scientific propaganda of the ideas of religious tolerance in the fight against such forces as terrorism and extremism in the world inspires hope for the stability of humanistic feelings in the sense of "science is salvation." [ABSTRACT FROM AUTHOR]

For the past two decades, the border conflict between Ethiopia and Eritrea has posed political, economic and social security threats in the Horn of Africa. The seemingly unexpected resurgence of jovial contact between Eritrea and Ethiopia grabbed national, regional and international attention. It was Abiy who jumpstarted the peace process in June 2018. Unfortunately, their relationship gradually deteriorated from a cheerful amorousness to a vicious enmity. Thus, Ethiopia and Eritrea have both shown the ability and readiness to utilise proxy armies against one another. However, the literature on Ethiopia–Eritrea relations now avoids the topic of how peace and security might be restored. Therefore, the primary goal of this article has been to discuss and analyse the development of the Ethio-Eritrean relationship since 2018, from jubilant liaison to paroxysm hostility. To record and analyse this exciting issue, the article would be limited to primary sources such as letters, reports, journals, interviews, live streaming media and published secondary texts that this writer has access to. [ABSTRACT FROM AUTHOR]

Optical Metasurfaces, two-dimensional nano-patterned surfaces designed to manipulate light, show promise for the sensitive detection of viruses. This paper reports on the development of a fractal plasmonic Metasurface tuned to operate in the near-infrared optical spectrum (2000–5000 nm) with Fano resonances. Fano resonances allow for sharper spectral features and higher sensitivity compared to typical plasmonic resonances. The Metasurface consists of a main ring containing self-similarly arranged nanoscale rings and disks while four smaller rings placed in the cardinal directions with five disks in the gaps between them. This fractal-like geometry exhibits enhanced light-matter interactions due to multiple electromagnetic hotspots in the structure. Specifically, simulations indicate the nanostructured sensor may enable label-free detection of viruses with high specificity by exploiting subtle changes in optical response when viral particles bind to receptors on the Metasurface. The simulation is done with full wave method of Finite integrated technique (FIT). The effect of the virus position over the Metasurface and its physical condition on the response of the Metasurface including the phase and amplitude is studied as a factor for sensing which can be used for optical imaging. • A highly sensitive biosensor based on a fractal plasmonic metasurface tuned to operate in the near-infrared optical spectrum (2000–5000 nm) with Fano resonances is designed. • Fano resonances allow for sharper spectral features and higher sensitivity compared to typical plasmonic resonances. • This fractal-like geometry exhibits enhanced light-matter interactions due to multiple electromagnetic hotspots in the structure. • This structure can be used for virus detection. [ABSTRACT FROM AUTHOR]

the mid-infrared metasurfaces play an important in optical applications including sensing and having Fano response is a benefit in this field for many goals including biosensing. So, these points are considered in this study and self-similar Plasmonic metasurface is suggested for sensing application. The suggested structure has a symmetrical formation but non-similar elements are considered to raise the Fano response. The structure contains five rings while the central one has a larger dimension than the four elements surrounding the central ring as an array of rings. The interaction of bright modes for both elements of the central ring and the array elements makes the Fano response at 1850 and 1910 nm while the single central ring has resonance at 1910 nm and the array rings have resonance at 1850 nm. The interaction of the element enhances the Q-factor of both resonances. The Full-wave method finite integrated technique (FIT) is used for modeling as a time domain method and the couple mother theory (CMT) is used for the analytical model. This metasurface is implemented as a sensor for detecting material under test and the sensitivity of the sensor is obtained 282 nm/RIU (Refractive Index Unit). Finally, the tissue of the liver as healthy and cancer cells are considered for examining the quality of the sensor. • The proposed design incorporates asymmetric ring elements inspired by self-similarity to induce Fano resonances. • Numerical simulations and analytical modeling demonstrate complete absorption at the target wavelengths of 1850 nm and 1910 nm. • A high sensitivity of 282 nm/RIU is attained owing to the narrow Fano resonance bandwidth. • The capability of this metasurface for non-invasive cancer detection and lab-on-chip integration is shown. • This paper provides an optimized design for plasmonic biosensors and results fitted with numerical model of the CMT. [ABSTRACT FROM AUTHOR]

Abstract We propose a planar metamaterial formed by four-strip metallic resonators, which can achieve high-Q Fano resonance in terahertz regime. This terahertz planar metamaterial supports a sharp Fano resonance at 0.81 THz with 25% transmission. The resonance bandwidth of the dip is 0.014 THz with the Q-factor of 58. The interference between the bright mode and dark mode leads to the Fano line shape. This sharp Fano profile is explained by the electromagnetic theory of Fano resonance. Moreover, multiple Fano resonances can be realized by adding more strips into the original structure. As an example, two Fano dips with Q-factors of 61 and 65 can be achieved via a five-strip structure.

We prove that a general determinantal hypersurface of dimension 3 is nodal. Moreover, in terms of Chern classes associated with bundle morphisms, we derive a formula for the intersection homology Euler characteristic of a general determinantal hypersurface. [ABSTRACT FROM AUTHOR]

Minimax lower bounds determine the complexity of given statistical problems by providing fundamental limit of any procedures. This paper gives a review on various aspects of obtaining minimax lower bounds focusing on a recent development. We first introduce classical methods, then more involved lower bound constructions such as testing two mixtures, two directional method, and global metric entropy method are provided with various examples including manifold learning, approximation sets and neural nets. In addition, we consider two different types of restrictions on the set of estimators. In particular, we consider the lower bounds when the set of estimators is required to be linear, and a private version of minimax lower bounds is discussed. [ABSTRACT FROM AUTHOR]

Purpose: This work introduces a new lattice geometry library, egs_lattice, into the EGSnrc Monte Carlo code, which can be used for both modeling very large (previously unfeasible) quantities of geometries (e.g., cells or gold nanoparticles (GNPs)) and establishing recursive boundary conditions. The reliability of egs_lattice, as well as EGSnrc in general, is cross‐validated and tested at short length scales and low energies. Methods: New Bravais, cubic, and hexagonal lattice geometries are defined in egs_lattice and their transport algorithms are described. Simulations of cells and GNP‐containing cavities are implemented to compare to independent, published Geant4‐DNA and PENELOPE results. Recursive boundary conditions, implemented through a cubic lattice, are used to perform electron Fano cavity tests. The Fano test is performed on three different‐sized cells containing GNPs in the region around the nucleus for three source energies. Results: Lattices are successfully implemented in EGSnrc, and are used for validation. EGSnrc calculated the dose to cell cytoplasm and nucleus when irradiated by an internal electron source with a median difference of 0.6% compared to published Geant4‐DNA results. EGSnrc calculated the ratio of dose to a microscopic cavity containing GNPs over dose to a cavity containing a homogeneous mixture of gold, and results generally agree (within 1%) with published PENELOPE results. The electron Fano cavity test is passed for all energies and cells considered, with sub‐0.1% discrepancies between EGSnrc‐calculated and expected values. Additionally, the recursive boundary conditions used for the Fano test provided a factor of over a million increase in efficiency in some cases. Conclusions: The egs_lattice geometry library, currently available as a pull request on the EGSnrc GitHub "develop" branch, is now freely accessible as open‐source code. Lattice geometry implementations cross‐validated with independent simulations in other MC codes and verified with the electron Fano cavity test demonstrate not only the reliability of egs_lattice, but also, by extension, EGSnrc's ability to simulate transport in nanometer geometries and score in microscopic cavities. [ABSTRACT FROM AUTHOR]

Most electromagnetic phenomena pertaining to metamaterials are observed at the resonance positions. In this review, we have collated and analyze the most prevalent forms of resonance-based phenomena observed in metamaterials to serve as a ready reference for future researchers. Our focus will be on metamaterials operating at the terahertz frequency domain. Starting with the origin and evolution of fundamental LC resonances in metamaterials, we would explain occurrence of typical even and odd higher order resonance modes. We have also discussed Fano resonances in asymmetric gap resonators-based metamaterials. Further, quantum phenomena analogues, such as, electromagnetically induced transparency (EIT) or Plasmon Induced Transparency (PIT), which can significantly influence the metamaterials resonances are also discussed. Thereafter, origins to ultra-sharp resonances in toroidal metamaterials, along with chiral metamaterials and resonance mode hybridization effects in the context of terahertz metamaterials are described. This review should be useful for undertaking. [ABSTRACT FROM AUTHOR]

In this paper, a nano-antenna with a Fano response is designed based on Heptamer array arrangement of Nano disks. Fano response formation for various arrangements of the nano-disks are investigated and finally, a multi-layer Heptamer structure is suggested and discussed. Moreover, the effect of multi-layers on the Fano response of Heptamer disks for different number of layers is fully studied. The proposed structure shows the hyperbolic metamaterial characteristic for the optical regime, which leads to near-filed performance enhancement. In this structure, polystyrene with refractive index between 1.59 and 2.4 is used as the kerr material to design a reconfigurable optical structure. Generally, in multi-layer structures, the total near field is strengthened up to 130 V/m resulting in a multi-Fano phenomenon. Finally, parametric study has been conducted to choose the best values. The final structure can be used as a sensor for material detection in the optical domain, achieving maximum sensitivity and Figure of Merit (FOM) of 513 nm/RIU and 117 RIU-1, respectively. [ABSTRACT FROM AUTHOR]

We present classical and recent results on Kähler-Einstein metrics on compact complex manifolds, focusing on existence, obstructions and relations to algebraic geometric notions of stability (K-stability). These are the notes for the SMI course "Kähler-Einstein metrics" given by C.S. in Cortona (Italy), May 2017. The material is not intended to be original.

Plasmonics is the field of study of the interaction between incident light and electrons in metals. It is used widely for developing nanophotonic devices. The structured metallic surface such as metamaterials can be used to produce spoof surface plasmons at any frequencies with the dimensions of unit cell less than the incident wavelength. Terahertz plasmonics is attracted to the field of research since it is used for sensing biological components even in a weak environment. The issue with planar metamaterials is a lower quality factor value. Several methods have been adopted for obtaining high Q-value in metamaterials. Among them, Fano- and Toroidal-based metamaterials offer high Q-factor and string localized field enhancement. This article discusses the importance and developments in the field of high-Q terahertz metamaterial for plasmonics applications. The nonlinear responses of terahertz metamaterial under high-intense THz pulses are also discussed. [ABSTRACT FROM AUTHOR]

High-Q metasurfaces have attracted much interest owing to their potential application in biological sensors. FANO is a type of high-Q factor metasurface. However, it is difficult to achieve large resonant intensity and a high-Q factor at the same time. In this paper, by sharpening the tips of the asymmetrical split-ring FANO structure and letting more charges stack at the tips to enhance tip coupling, the Q factor was significantly improved without sacrificing too much resonant intensity. Simulation results showed that the Q factor increased up to 2.4 times, while the resonant intensity stayed higher than 20 dB, and the experiment results agreed with the simulations. This indicated that the tip-field-enhancement theory can be applied in time-harmonic electromagnetic-fields, and the method proposed here can be used to increase the sensitivity and accuracy of microfluidic sensors. Additionally, other types of research, such as on antenna design, could benefit from this theory. [ABSTRACT FROM AUTHOR]

Highlights • Hybrid graphene double bar shows large modulation depth and Q -factors. • The Q -factor of Fano resonant curves is more than 20 in the THz regime. • By changing graphene Fermi level, the frequency modulation depth is about 60%. Abstract Based on the hybrid metal-graphene structures, we investigated the tunable Fano resonances in the terahertz region, including the effects of graphene Fermi levels, structural parameters, and operation frequencies. The results reveal that an obvious Fano resonance can be observed, the maximum peak value of Fano resonance can reach 0.9711, and its Q -quality factor is more about 20. With the help of the graphene layer, the resonant curves of the proposed structures can be effectively modulated, the frequency modulation depth can reach 60% as the Fermi level changes in the range of 0.1–1.0 eV. In addition, by varying the length of graphene bar in the scope of 10–60 μm, the amplitude modulation depths are about 21.0%. The results are helpful for designing novel graphene-based tunable terahertz devices with high Q factor, e.g. modulators, sensors and antenna. [ABSTRACT FROM AUTHOR]

Guided mode resonances (GMR) in a planar compound metamaterial (MM) consisting of two square closed ring resonators were numerically calculated and experimentally demonstrated. The strength and bandwidth of the GMR can be controlled by changing the distance between the two square rings. Moreover, asymmetric Fano resonance or electromagnetic induced transparency (EIT) was realized by manipulating the interaction between the GMR and the dipolar resonance of the MM. The measured results at terahertz frequencies are in good agreement with simulations. [ABSTRACT FROM AUTHOR]

High-Q metasurfaces have attracted much interest owing to their potential application in biological sensors. FANO is a type of high-Q factor metasurface. However, it is difficult to achieve large resonant intensity and a high-Q factor at the same time. In this paper, by sharpening the tips of the asymmetrical split-ring FANO structure and letting more charges stack at the tips to enhance tip coupling, the Q factor was significantly improved without sacrificing too much resonant intensity. Simulation results showed that the Q factor increased up to 2.4 times, while the resonant intensity stayed higher than 20 dB, and the experiment results agreed with the simulations. This indicated that the tip-field-enhancement theory can be applied in time-harmonic electromagnetic-fields, and the method proposed here can be used to increase the sensitivity and accuracy of microfluidic sensors. Additionally, other types of research, such as on antenna design, could benefit from this theory.

The detection of fluorescence with submolecular resolution enables the exploration of spatially varying photon yields and vibronic properties at the single-molecule level. By placing individual polycyclic aromatic hydrocarbon molecules into the plasmon cavity formed by the tip of a scanning tunneling microscope and a NaCl-covered Ag(111) surface, molecular light emission spectra are obtained that unravel vibrational progression. In addition, light spectra unveil a signature of the molecule even when the tunneling current is injected well separated from the molecular emitter. This signature exhibits a distance-dependent Fano profile that reflects the subtle interplay between inelastic tunneling electrons, the molecular exciton and localized plasmons in at-distance as well as on-molecule fluorescence. The presented findings open the path to luminescence of a different class of molecules than investigated before and contribute to the understanding of single-molecule luminescence at surfaces in a unified picture. [ABSTRACT FROM AUTHOR]

El objetivo de este artículo es dar a conocer un ejemplar del primer libro impreso en caracteres árabes con tipos móviles, Kitāb Ṣalāẗ al-sawa'i, Fano, 1514, conservado en la Biblioteca Histórica "Marqués de Valdecilla", de la Universidad Complutense de Madrid, y que constituye uno de los pocos ejemplares que se conocen en el mundo de este título, tan solo 15. Se hace un estudio de la planificación de la obra, de los cuadernillos que lo componen, de las distintas decoraciones que presenta y del ritmo tipográfico en su composición y del impresor, Gregorio de Gregorio. El artículo se completa con un breve estudio de su contenido, un libro de horas dirigido a los cristianos de Oriente, y se indican los capítulos y las horas que corresponden. Se realiza por fin un censo de los ejemplares conocidos en bibliotecas de Europa, Estados Unidos y Egipto. The aim of this article is to give known an specimen of the first Arabic printed book by movable type, Kitāb Ṣalāẗ al-sawa'i, Fano 1514, which is kept at the Biblioteca Histórica "Marqués de Valdecilla", of the Universidad Complutense de Madrid and which is one of the few volumes known in the world of this title, only 15. For this purpose, the general planning of the book, the number of the quaternion, the different decorative patterns of the page opening chapters, the typographical rhythm of the composition and the printer, Gregorio de Gregorio is being studied. The article is completed with a brief explanation of the content, a book of hours planned to be addressed to the Christians of Orient, and chapters and hours of the book are studied. For finishing, a census of the existing volumes remaining in libraries of Europe, United States and Egypt is made.

Chiral metamaterials with asymmetric transmission can be applied as polarization-controlled devices. Here, a Mie-based dielectric metamaterial with a spacer exhibiting asymmetric transmission of linearly polarized waves at microwave frequencies was designed and demonstrated numerically. The unidirectional characteristic is attributed to the chirality of the metamolecule and the mutual excitation of the Mie resonances. Field distributions are simulated to investigate the underlying physical mechanism. Fano-type resonances emerge near the Mie resonances of the constituents and come from the destructive interference inside the structure. The near-field coupling further contributes to the asymmetric transmission. The influences of the lattice constant and the spacer thickness on the asymmetric characteristics were also analyzed by parameter sweeps. The proposed Mie-based metamaterial is of a simple structure, and it has the potential for applications in dielectric metadevices, such as high-performance polarization rotators.