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Related papers: Valley-polarization in biased bilayer graphene usi…

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We study the electronic transmission through a graphene bilayer in the presence of an applied bias between layers. We consider different geometries involving interfaces between both a monolayer and a bilayer and between two bilayers. The…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Johan Nilsson , A. H. Castro Neto , F. Guinea , N. M. R. Peres

The tunnel current (TC) and valley current (VC) are crucial in realizing high-speed and energy-saving in next-generation devices. This paper presents the TC and VC link in the partially overlapped graphene. Under the vertical electric…

Mesoscale and Nanoscale Physics · Physics 2025-07-11 Ryo Tamura

The exquisite distortion in a Kekul\'e-Y (Kek-Y) superlattice merges the two inequivalent Dirac cones (from the $K$- and the $K^\prime$- points) into the highest symmetric $\Gamma$-point in the hexagonal Brillouin zone. Here we report that…

Mesoscale and Nanoscale Physics · Physics 2024-10-08 Sushmita Saha , Alestin Mawrie

An analogue of the Datta-Das spin FET is investigated, which is all-graphene and based on the valley degree of freedom of electrons / holes. The "valley FET" envisioned consists of a quantum wire of gapped graphene (channel) sandwiched…

Mesoscale and Nanoscale Physics · Physics 2013-01-01 M. -K. Lee , N. -Y. Lue , Y. -C. Chen , C. -K. Wen , G. Y. Wu

The circular polarization (CP) that the photoluminescence inherits from the excitation source in n monolayers of transition-metal dichalcogenides (MX2)n has been previously explained as a special feature of odd values of n, where the…

Materials Science · Physics 2015-03-02 Qihang Liu , Xiuwen Zhang , Alex Zunger

We consider coherent dynamics of graphene charged carriers exposed to an intense few-cycle linearly polarized laser pulse. The results, obtained by solving the generalized semiconductor Bloch equations numerically in the Hartree-Fock…

In graphene, a Kekul\'e-Y bond texture modifies the electronic band structure generating two concentric Dirac cones with different Fermi velocities lying in the {\Gamma}-point in reciprocal space. The energy dispersion results in different…

Mesoscale and Nanoscale Physics · Physics 2022-11-23 Elias Andrade , Ramon Carrillo-Bastos , Mahmoud M. Asmar , Gerardo G. Naumis

Valley degrees of freedom in transition-metal dichalcogenides influence thoroughly electron-phonon coupling and its nonequilibrium dynamics. We conducted a first-principles study of the quantum kinetics of chiral phonons following…

Mesoscale and Nanoscale Physics · Physics 2023-08-16 Yiming Pan , Fabio Caruso

We analyze density-wave and Pomeranchuk orders in twisted bilayer graphene. This compliments our earlier analysis of the pairing instabilities. We assume that near half-filling of either conduction or valence band, the Fermi level is close…

Strongly Correlated Electrons · Physics 2020-09-18 Dmitry V. Chichinadze , Laura Classen , Andrey V. Chubukov

Electron's tunneling through potential barrier in monolayer and bilayer graphene lattices is investigated by using full tight-binding model. Emphasis is placed on the resonance tunneling feature and inter-valley scattering probability. It…

Mesoscale and Nanoscale Physics · Physics 2008-08-25 Di Wu , Weiqiang Chen , Fu-Chun Zhang

We investigate superconducting pairing tendencies of a two-dimensional electron fluid with both valley and spin degrees of freedom, both without and in the presence of an in-plane magnetic field. We present suggestive theoretical arguments…

Superconductivity · Physics 2022-04-04 Zhaoyu Han , Steven A. Kivelson

Strongly interacting two dimensional electron systems (2DESs) host a complex landscape of broken symmetry states. The possible ground states are further expanded by internal degrees of freedom such as spin or valley-isospin. While direct…

Mesoscale and Nanoscale Physics · Physics 2017-11-01 B. M. Hunt , J. I. A. Li , A. A. Zibrov , L. Wang , T. Taniguchi , K. Watanabe , J. Hone , C. R. Dean , M. Zaletel , R. C. Ashoori , A. F. Young

We investigate physical properties that can be used to distinguish the valley degree of freedom in systems where inversion symmetry is broken, using graphene systems as examples. We show that the pseudospin associated with the valley index…

Materials Science · Physics 2011-11-10 Di Xiao , Wang Yao , Qian Niu

We develop a theory of circular photogalvanic effect in non-gyrotropic two-dimensional transition metal dichalcogenide monolayers under interband optical transitions. Oblique incidence of circularly-polarized electromagnetic field or normal…

Mesoscale and Nanoscale Physics · Physics 2021-08-18 M. V. Entin , V. M. Kovalev

Superior to ferromagnetic (FM) valleytronics, antiferromagnetic (AFM) counterpart exhibits ultradense and ultrafast potential due to their intrinsic advantages of zero stray field, terahertz dynamics, and compensated moment of…

Materials Science · Physics 2024-11-12 San-Dong Guo , Ping Li , Guangzhao Wang

The illumination of a single-layer transition metal dichalcogenide with an elliptically-polarized light beam is shown to give rise to a differential rate of inter-band carrier excitation between the valence and conduction states around the…

Materials Science · Physics 2017-03-28 Parijat Sengupta , Yaohua Tan , Dmitris Pavlidis , Junxia Shi

We investigate the electronic dispersion and transport properties of graphene/WSe$_{2}$ heterostructures in the presence of a proximity-induced spin-orbit coupling $\lambda_{v}$, sublattice potential $\Delta$, and an off-resonant circularly…

Mesoscale and Nanoscale Physics · Physics 2023-07-07 M. Zubair , P. Vasilopoulos , M. Tahir

Two-dimensional semiconductors feature valleytronics phenomena due to locking of the spin and momentum valley of the electrons. However, the valley polarization is intrinsically limited in monolayer crystals by the fast intervalley…

Mesoscale and Nanoscale Physics · Physics 2019-07-10 Long Zhang , Rahul Gogna , G. William Burg , Jason Horng , Eunice Paik , Yu-Hsun Chou , Kyounghwan Kim , Emanuel Tutuc , Hui Deng

New phase of matter usually emerges when a given symmetry breaks spontaneously, which can involve charge, spin, and valley degree of freedoms. Here, we report an observation of new correlated insulators evolved from spin polarized states to…

Monolayer Graphene contains two inequivalent local minimum, valleys, located at $K$ and $K'$ in the Brillouin zone. There has been considerable interest in the use of these two valleys as a doublet for information processing. Herein I…

Mesoscale and Nanoscale Physics · Physics 2020-06-02 Samuel Bladwell