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Related papers: Photo-induced valley currents in strained graphene

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When graphene is deformed in a dynamical manner, a time-dependent potential is induced for the electrons. The potential is antisymmetric with respect to valleys, and some straightforward applications are found for Raman spectroscopy. We…

Mesoscale and Nanoscale Physics · Physics 2014-11-17 Ken-ichi Sasaki , Yasuhiro Tokura , Hideki Gotoh

The generation of a fully valley-polarized current (FVPC) in bulk graphene is a fundamental goal in valleytronics. To this end, we investigate valley-dependent transport through a strained graphene modulated by a finite magnetic…

Mesoscale and Nanoscale Physics · Physics 2013-11-04 Yu Song , Feng Zhai , Yong Guo

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

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

We examine the full static non-linear optical response of uniaxially strained transition metal dichalcogenide monolayers doped with a finite carrier density in the conduction band, in the presence of disorder. We find that the customary…

Mesoscale and Nanoscale Physics · Physics 2022-05-23 Reza Asgari , Dimitrie Culcer

Spontaneous optical emission of graphene irradiated by intense single-cycle terahertz pulses was investigated experimentally and explained theoretically. We found that emitted photons are polarized predominantly perpendicular to the…

Mesoscale and Nanoscale Physics · Physics 2022-11-23 I. V. Oladyshkin , S. B. Bodrov , A. V. Korzhimanov , A. A. Murzanev , Yu. A. Sergeev , A. I. Korytin , M. D. Tokman , A. N. Stepanov

Magic-angle twisted bilayer graphene displays a complex phase diagram as a function of flat band filling, featuring compressibility cascade transitions and a variety of competing ground states with broken spin, valley and point group…

Mesoscale and Nanoscale Physics · Physics 2026-01-29 Fernando Peñaranda , Héctor Ochoa , Fernando de Juan

DC photoelectrical currents can be generated purely as a non-linear effect in uniform media lacking inversion symmetry without the need for a material junction or bias voltages to drive it, in what is termed photogalvanic effect. These…

Mesoscale and Nanoscale Physics · Physics 2016-08-17 F. Hipolito , Thomas G. Pedersen , Vitor M. Pereira

We recently shown, using tight-binding calculations, that nonequilibrium valley polarization can be realized in graphene, when the current is injected through "valley filter": a ballistic point contact with zigzag edges. Here we…

Mesoscale and Nanoscale Physics · Physics 2008-05-23 Adam Rycerz

We examine the photoconductivity of an intrinsic graphene associated with far- and mid-infrared irradiation at low temperatures. The model under consideration accounts for the excitation of the electron-hole pairs by incident radiation, the…

Materials Science · Physics 2008-05-27 F. T. Vasko V. Ryzhii

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

We present a single barrier system to generate pure valley-polarized current in monolayer graphene. A uniaxial strain is applied within the barrier region, which is delineated by localized magnetic field created by ferromagnetic stripes at…

Mesoscale and Nanoscale Physics · Physics 2016-03-07 Can Yesilyurt , Seng Ghee Tan , Gengchiau Liang , Mansoor B. A. Jalil

The valley degree of freedom in 2D materials can be manipulated for low-dissipation quantum electronics called valleytronics. At the boundary between two regions of bilayer graphene with different atomic or electrostatic configuration,…

Mesoscale and Nanoscale Physics · Physics 2024-04-03 Konstantin Davydov , Xi Zhang , Wei Ren , Matthew Coles , Logan Kline , Bryan Zucker , Kenji Watanabe , Takashi Taniguchi , Ke Wang

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

The extreme mechanical resilience of graphene and the peculiar coupling it hosts between lattice and electronic degrees of freedom have spawned a strong impetus towards strain-engineered graphene where, on the one hand, strain augments the…

Mesoscale and Nanoscale Physics · Physics 2017-08-16 Gareth W. Jones , D. A. Bahamon , A. H. Castro Neto , Vitor M. Pereira

We consider the corrugated monolayer graphene membrane electromagnetic (from both valleys) response in terahertz range. We study the generated in irradiated graphene total current for the first time taking into account both the synthetic…

Mesoscale and Nanoscale Physics · Physics 2014-02-14 Yu. A. Firsov , N. E. Firsova

Valleytronics has been widely investigated for providing new degrees of freedom to future information coding and processing. Here, it is proposed that valley polarization can be achieved by electric field induced magnetic anisotropy (MA)…

Materials Science · Physics 2022-08-05 San-Dong Guo , Xiao-Shu Guo , Guang-Zhao Wang , Kai Cheng , Yee-Sin Ang

We present a framework to calculate the anisotropic and non-linear photoconductivity for two band systems with application to graphene. In contrast to the usual perturbative (second order in the optical field strength) techniques, we…

Mesoscale and Nanoscale Physics · Physics 2018-01-10 Ashutosh Singh , Saikat Ghosh , Amit Agarwal

We propose a scheme to trap and filter electrons, valley dependently, on a scale beyond the diffraction limit, in a gapped Dirac system using a circularly polarized light beam and a microscale metallic resonator. The main mechanism allowing…

Mesoscale and Nanoscale Physics · Physics 2019-01-23 Kevin Dini , Ivan V. Iorsh , Andrey Bogdanov , Ivan A. Shelykh

Persistent currents can arise in normal-metal rings due to a magnetic flux threading the ring in equilibrium. However, can persistent currents arise in absence of magnetic flux in the same normal-metal rings? Yes they can but in a…

Mesoscale and Nanoscale Physics · Physics 2014-02-07 Colin Benjamin , A M Jayannavar