English
Related papers

Related papers: Photo-induced valley currents in strained graphene

200 papers

It is quite easy to control spin polarization and spin direction of a system via magnetic fields. However, there is no such a direct and efficient way to manipulate valley pseudospin degree of freedom. Here, we demonstrate experimentally…

Mesoscale and Nanoscale Physics · Physics 2020-03-18 Si-Yu Li , Ying Su , Ya-Ning Ren , Lin He

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

Strain engineering is a promising approach for suppressing the OFF-state conductance in graphene-based devices that arises from Klein tunnelling. In this work, we derive a comprehensive tight-binding Hamiltonian for strained graphene that…

Mesoscale and Nanoscale Physics · Physics 2021-08-25 Maverick Chauwin , Zhuo Bin Siu , Mansoor Bin Abdul Jalil

Using the tight-binding model, we investigate the valley current of the `low-bi-up' and `low-bi-low' graphene junction, where `low' and `up' are respectively the lower and upper graphene layers extended from the central AB stacking bilayer…

Mesoscale and Nanoscale Physics · Physics 2023-11-01 Ryo Tamura

The long-wavelength physics of monolayer graphene in the presence of periodic strain fields has a natural chiral scattering network description. When the strain field varies slowly compared to the graphene lattice and the effective magnetic…

Mesoscale and Nanoscale Physics · Physics 2023-01-18 Christophe De Beule , Vo Tien Phong , E. J. Mele

We study theoretically the electron current across a monolayer graphene/hexagonal boron nitride/bilayer graphene tunnelling junction in an external magnetic field perpendicular to the layers. We show that change in effective tunnelling…

Mesoscale and Nanoscale Physics · Physics 2019-02-18 J. J . P. Thompson , D. J. Leech , M. Mucha-Kruczyński

We show the possibility of inducing an edge charge current by applying time-dependent strain in gapped graphene samples preserving time reversal symmetry. We demonstrate that this edge current has the same origin as the valley Hall response…

Mesoscale and Nanoscale Physics · Physics 2015-05-28 Abolhassan Vaezi , Nima Abedpour , Reza Asgari , Alberto Cortijo , María A. H. Vozmediano

Graphene is a promising candidate for optoelectronic applications such as photodetectors, terahertz imagers, and plasmonic devices. The origin of photoresponse in graphene junctions has been studied extensively and is attributed to either…

Mesoscale and Nanoscale Physics · Physics 2013-01-30 Marcus Freitag , Tony Low , Fengnian Xia , Phaedon Avouris

The interband and intraband conductivities of doped graphene were theoretically investigated beyond the linear response. The new dependences of induced currents on frequency and amplitude of external electric field, the graphene temperature…

Mesoscale and Nanoscale Physics · Physics 2013-08-19 B. M. Ruvinskii , M. A. Ruvinskii

Quantum transport calculations describing electron scattering off an extended line defect in graphene are presented. The calculations include potentials from local magnetic moments recently predicted to exist on sites adjacent to the line…

Mesoscale and Nanoscale Physics · Physics 2012-05-18 Daniel Gunlycke , Carter T. White

Well established for the visible spectrum gaps of the transition metal dichalcogenide family, valleytronics - the control of valley charge and current by light - is comparatively unexplored for the THz gaps that characterize graphene and…

Mesoscale and Nanoscale Physics · Physics 2025-07-01 Deepika Gill , Sangeeta Sharma , Sam Shallcross

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

We theoretically analyze the nonlinear valley Nernst effect (NVNE) as the second-order response of temperature gradient through the semiclassical framework of electron dynamics. Our study shows that an intrinsic nonlinear pure valley…

Mesoscale and Nanoscale Physics · Physics 2025-10-08 Ying-Li Wu , Jia-Liang Wan , Xiao-Qin Yu

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

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

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 calculate the photocurrent in a clean graphene sample normally irradiated by a monochromatic electromagnetic field and subject to a step-like electrostatic potential. We consider the photon energies $\hbar\Omega$ that significantly…

Mesoscale and Nanoscale Physics · Physics 2011-02-04 S. Mai , S. V. Syzranov , K. B. Efetov

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

Modulation of electronic states in two-dimensional (2D) materials can be achieved by using in-plane variations of the band gap or the average potential in lateral quantum structures. In the atomic configurations with hexagonal symmetry,…

Mesoscale and Nanoscale Physics · Physics 2016-08-10 Feng-Wu Chen , Mei-Yin Chou , Yiing-Rei Chen , Yu-Shu Wu

In the last decade, advancements in attosecond spectroscopy have allowed us to study electron motion dynamics in condensed matter. The access to these electron dynamics and, consequently, its control by an ultrafast light field paves the…

Mesoscale and Nanoscale Physics · Physics 2025-05-12 Mohamed Sennary , Jalil Shah , Mingrui Yuan , Ahmed Mahjoub , Vladimir Pervak , Nikolay Golubev , Mohammed Hassan