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Related papers: Strain controlled valley filtering in multi-termin…

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We show how the trigonal warping effect in doped graphene can be used to produce fully valley polarized currents. We propose a device that acts both as a beam splitter and a collimator of these electronic currents. The result is…

Mesoscale and Nanoscale Physics · Physics 2007-10-05 J. L. Garcia-Pomar , A. Cortijo , M. Nieto-Vesperinas

Valley filters are crucial to any device exploiting the valley degree of freedom. By using an atomistic model, we analyze the mechanism leading to the valley filtering produced by a line-defect in graphene and show how it can be inverted by…

Mesoscale and Nanoscale Physics · Physics 2016-10-11 Lucas H. Ingaramo , Luis E. F. Foa Torres

We propose an all-electrical setup to generate valley polarization in graphene. A finite graphene sheet is connected to two normal metal electrodes each with two terminals along its zigzag edges, while the armchair edges remain free. When a…

Mesoscale and Nanoscale Physics · Physics 2025-06-30 Sachchidanand Das , Abhiram Soori

Analogous to charge and spin, electrons in solids endows an additional degree of freedom: the valley pseudospin. Two-dimensional hexagonal materials such as graphene exhibit two valleys, labelled as $\mathbf{K}$ and $\mathbf{K}^{\prime}$.…

Mesoscale and Nanoscale Physics · Physics 2022-01-12 M. S. Mrudul , Gopal Dixit

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

Mechanical deformations in $\alpha$-$\mathcal{T}_3$ lattices induce local pseudomagnetic fields of opposite directionality for different valleys. When this strain is equipped with a dynamical drive, it generates a complementary…

Mesoscale and Nanoscale Physics · Physics 2022-12-07 Alexander Filusch , Holger Fehske

Low-energy excitations in graphene exhibit relativistic properties due to the linear dispersion relation close to the Dirac points in the first Brillouin zone. Two of the Dirac points located at opposite corners of the first Brillouin zone…

Mesoscale and Nanoscale Physics · Physics 2017-05-25 T. Sekera , C. Bruder , E. J. Mele , R. P. Tiwari

The existence of two-inequivalent valleys in the band structure of graphene has motivated the search of mechanisms that allow their separation and control for potential device applications. Among the several schemes proposed in the…

Mesoscale and Nanoscale Physics · Physics 2018-10-31 Dawei Zhai , Nancy Sandler

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

The generation of valley current is a fundamental goal in graphene valleytronics but no practical ways of its realization are known yet. We propose a workable scheme for the generation of bulk valley current in a graphene mechanical…

Mesoscale and Nanoscale Physics · Physics 2013-01-25 Yongjin Jiang , Tony Low , Kai Chang , Mikhai I. Katsnelson , Francisco Guinea

Producing currents predominantly from a single valley, namely valley-polarized currents, at optical-cycle timescales is an important aspect of the petahertz valleytronics, yet it remains less developed. This work exhibits the feasibility of…

Optics · Physics 2025-03-13 Wenqing Li , Xiaosong Zhu , Liang Li , Wanzhu He , Jie Long , Pengfei Lan , Peixiang Lu

In addition to electron charge and spin, novel materials host another degree of freedom, the valley. For a junction composed of valley filter sandwiched by two normal terminals, we focus on the valley efficiency under disorder with two…

Mesoscale and Nanoscale Physics · Physics 2017-11-29 Shu-guang Cheng , Jiaojiao Zhou , Hua Jiang , Qing-Feng Sun

Probing and controlling the valley degree of freedom in graphene systems by transport measurements has been a major challenge to fully exploit the unique properties of this two-dimensional material. In this theoretical work, we show that…

Mesoscale and Nanoscale Physics · Physics 2022-11-09 Feng-Wu Chen , Nin-Yuan Lue , Mei-Yin Chou , Yu-Shu G. Wu

Recent experiments have revealed that novel nonequilibrium states consistent with the hydrodynamic description of electrons are realized in ultrapure graphene, which hosts the valley degrees of freedom. Here, we formulate a theory of…

Mesoscale and Nanoscale Physics · Physics 2022-05-05 Ryotaro Sano , Daigo Oue , Mamoru Matsuo

We propose a directional switching effect in a metallic device. To such end we exploit a graphene-based device with a three-terminal geometry in the presence of a magnetic field. We show that unidirectional charge and valley currents can be…

Mesoscale and Nanoscale Physics · Physics 2018-12-12 M. Berdakin , J. E. Barrios Vargas , L. E. F. Foa Torres

We test the valley-filtering capabilities of a quantum dot inscribed by locally straining an $\alpha$-$\mathcal{T}_3$ lattice. Specifically, we consider an out-of-plane Gaussian bump in the center of a four-terminal configuration and…

Mesoscale and Nanoscale Physics · Physics 2021-04-16 Alexander Filusch , Alan R. Bishop , Avadh Saxena , Gerhard Wellein , Holger Fehske

We report on the possibility to simultaneously generate in graphene a {\it bulk valley-polarized dissipative transport} and a {\it quantum valley Hall effect} by combining strain-induced gauge fields and real magnetic fields. Such unique…

Mesoscale and Nanoscale Physics · Physics 2018-08-01 Mikkel Settnes , José Hugo García , Stephan Roche

We study the electron scattering produced by local out-of-plane strain deformations in the form of Gaussian bumps in graphene. Of special interest is to take into account the scalar field associated with the redistribution of charge due to…

Mesoscale and Nanoscale Physics · Physics 2018-10-30 Ramon Carrillo-Bastos , Marysol Ochoa , Saúl A. Zavala , Francisco Mireles

Achieving a population imbalance between the two inequivalent valleys is a critical first step for any valleytronic device. A valley-polarization can be induced in biased bilayer graphene using circularly polarized light. In this paper, we…

Mesoscale and Nanoscale Physics · Physics 2021-02-17 Alex Friedlan , Marc M. Dignam

In strained graphene, lattice deformation can create pseudo-magnetic fields and result in zero-field Landau level-like quantization. In the presence of an external magnetic field, valley-polarized Landau levels are predicted to be observed…

Mesoscale and Nanoscale Physics · Physics 2015-12-16 Si-Yu Li , Ke-Ke Bai , Long-Jing Yin , Jia-Bin Qiao , Wen-Xiao Wang , Lin He