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Related papers: Optical valleytronics in gapped graphene

200 papers

The paper presents a theoretical description of the effects of strain induced by out-of-plane deformations on charge distributions and transport on graphene. A review of a continuum model for electrons using the Dirac formalism is…

Mesoscale and Nanoscale Physics · Physics 2019-10-15 Dawei Zhai , Nancy Sandler

Selective control over the emission pattern of valley-polarized excitons in monolayer transition metal dichalcogenides is crucial for developing novel valleytronic, quantum information, and optoelectronic devices. While significant progress…

Motivated by recent experiments in weakly hybridized small-angle twisted bilayer graphene, we investigate how valley imbalance affects the viscosity of two-dimensional Dirac fluids. We show that shifting the two low-energy Dirac cones…

Mesoscale and Nanoscale Physics · Physics 2026-05-13 Alexey Ermakov , Alessandro Principi

We consider a lateral hetero-junction where the left and right leads are made of monolayer graphene and the middle region is made of a gapped tilted Dirac material (borophene or quinoid graphene) illuminated with off-resonant circularly…

Mesoscale and Nanoscale Physics · Physics 2020-07-22 Priyadarshini Kapri , Bashab Dey , Tarun Kanti Ghosh

Plasma photonic crystals designed in this paper are composed of gas discharge tubes to control the flow of electromagnetic waves. The band structures calculated by the finite element method are consistent with the experimental results in…

We show analytically that the ability of Dirac materials to localize an electron in both a barrier and a well can be utilized to open a pseudo-gap in graphene's spectrum. By using narrow top-gates as guiding potentials, we demonstrate that…

Mesoscale and Nanoscale Physics · Physics 2020-11-17 R. R. Hartmann , M. E. Portnoi

Graphene, and other members of the monolayer Xene family, represent an ideal materials platform for "valleytronics", the control of valley localized charge excitations. The absence of a gap in these semi-metals, however, precludes valley…

We study transport across p-n junctions of gapped two-dimensional semi-Dirac materials: nodal semimetals whose energy bands disperse quadratically and linearly along distinct crystal axes. The resulting electronic properties --- relevant to…

Mesoscale and Nanoscale Physics · Physics 2017-07-26 K. Saha , R. Nandkishore , S. A. Parameswaran

We study the tunneling of chiral electrons in graphene through a region where the electronic spectrum changes from the usual linear dispersion to a hyperbolic dispersion, due to the presence of a gap. It is shown that contrary to the…

Mesoscale and Nanoscale Physics · Physics 2008-07-09 J. Viana Gomes , N. M. R. Peres

We describe an angularly asymmetric interface-scattering mechanism which allows to spatially separate the electrons in the two low-energy valleys of bilayer graphene. The effect occurs at electrostatically defined interfaces separating…

Mesoscale and Nanoscale Physics · Physics 2010-11-05 Henning Schomerus

Gapped 2D Dirac materials, in which inversion symmetry is broken by a gap-opening perturbation, feature a unique valley transport regime. The system ground state hosts dissipationless persistent valley currents existing even when…

Mesoscale and Nanoscale Physics · Physics 2015-09-22 Yuri D. Lensky , Justin C. W. Song , Polnop Samutpraphoot , Leonid S. Levitov

For gapped graphene, we predict that an intense ultrashort (single-oscillation) circularly-polarized optical pulse can induce a large population of the conduction band and a large valley polarization. With an increase in the bandgap, the…

Mesoscale and Nanoscale Physics · Physics 2019-09-25 S. Azar Oliaei Motlagh , Fatemeh Nematollahi , Vadym Apalkov , Mark I. Stockman

High-mobility graphene hosting massless charge carriers with linear dispersion provides a promising platform for electron optics phenomena. Inspired by the physics of dielectric optical micro-cavities where the photon emission…

Mesoscale and Nanoscale Physics · Physics 2022-12-15 Jule-Katharina Schrepfer , Szu-Chao Chen , Ming-Hao Liu , Klaus Richter , Martina Hentschel

The application of a perpendicular electric field can drive silicene into a gapless state, characterized by two nearly fully spin-polarized Dirac cones owing to both relatively large spin-orbital interactions and inversion symmetry…

Mesoscale and Nanoscale Physics · Physics 2013-09-30 Yan-Yang Zhang , Wei-Feng Tsai , Kai Chang , X. -T. An , G. -P. Zhang , X. -C. Xie , Shu-Shen Li

The possibility to effect valley splitting of an electronic current in graphene represents the essential component in the new field of valleytronics in such two-dimensional materials. Based on a symmetry analysis of the scattering matrix,…

Mesoscale and Nanoscale Physics · Physics 2017-11-22 Mahmoud M. Asmar , Sergio E. Ulloa

Exact stationary solutions of the electron-photon Dirac equation are obtained to describe the strong interaction between massless Dirac fermions in graphene and circularly polarized photons. It follows from them that this interaction forms…

Mesoscale and Nanoscale Physics · Physics 2010-04-26 O. V. Kibis

We consider resonant scatterers with large scattering cross-sections in graphene that are produced by a gated disk or a vacancy, and show that a gated ring can be engineered to produce an efficient electron cloak. We also demonstrate that…

Mesoscale and Nanoscale Physics · Physics 2015-04-23 Diego Oliver , Jose H. Garcia , Tatiana G. Rappoport , N. M. R. Peres , Felipe A. Pinheiro

Realizations of some topological phases in two-dimensional systems rely on the challenge of jointly incorporating spin-orbit and magnetic exchange interactions. Here, we predict the formation and control of a fully valley-polarized quantum…

Mesoscale and Nanoscale Physics · Physics 2021-10-25 Marc Vila , Jose H. Garcia , Stephan Roche

We demonstrated theoretically that the renormalization of the electron energy spectrum near the Dirac point of graphene by a strong high-frequency electromagnetic field (dressing field) drastically depends on polarization of the field.…

Mesoscale and Nanoscale Physics · Physics 2016-02-04 K. Kristinsson , O. V. Kibis , S. Morina , I. A. Shelykh

This work performs a numerical study of electron transport through the fundamental logic gate in valleytronics - a valley valve consisting of two or increasing number of valley filters. Various typical effects on the transport are…

Mesoscale and Nanoscale Physics · Physics 2022-11-09 Jia-Huei Jiang , Ning-Yuan Lue , Feng-Wu Chen , Yu-Shu G. Wu