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Related papers: Light-Induced Valleytronics in Pristine Graphene

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The valley degree of freedom of electrons in materials promises routes toward energy-efficient information storage with enticing prospects towards quantum information processing. Current challenges in utilizing valley polarization are…

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

The selective control of specific momentum valleys lies at the core of valleytronics, a field that has thus far focused primarily on the $\mathbf{K}$ and $\mathbf{K'}$ valleys in transition metal dichalcogenides (TMDs). However, direct…

Strongly Correlated Electrons · Physics 2026-05-05 Youngjae Kim

Low energy valleys in the band structure of 2d materials represent a potential route to the ultrafast writing of information in quantum matter by laser light, with excited charge at the K or K$^\ast$ valleys representing the fundamental…

Mesoscale and Nanoscale Physics · Physics 2025-10-30 Sangeeta Sharma , Deepika Gill , John Kay Dewhurst , Peter Elliott , Sam Shallcross

Valley, the energy extrema in the electronic band structure at momentum space, is regarded as a new degree of freedom of electrons, in addition to charge and spin. The studies focused on valley degree of freedom now form an emerging field…

Materials Science · Physics 2020-02-13 He Hu , Wen-Yi Tong , Yu-Hao Shen , Xiangang Wan , Chun-Gang Duan

The band structure of transition metal dichalcogenides (TMDCs) with valence band edges at different locations in the momentum space could be harnessed to build devices that operate relying on the valley degree of freedom. To realize such…

Mesoscale and Nanoscale Physics · Physics 2016-09-06 Oriol Lopez Sanchez , Dmitry Ovchinnikov , Shikhar Misra , Adrien Allain , Andras Kis

Elastic deformations of graphene can significantly change the flow paths and valley polarization of the electric currents. We investigate these phenomena in graphene nanoribbons with localized out-of-plane deformations by means of…

Mesoscale and Nanoscale Physics · Physics 2019-03-12 Thomas Stegmann , Nikodem Szpak

We demonstrate valley-dependent vortex generation in a photonic graphene. Without breaking the inversion symmetry, excitation of two equivalent valleys leads to formation of an optical vortex upon Bragg-reflection to the third valley, with…

Graphene on hBN (G/hBN) has a long period moir\'{e} superstructure owing to the lattice mismatch between two materials. Long periodic potential caused by the moir\'{e} superstructure induces modulation of electronic properties of the…

Mesoscale and Nanoscale Physics · Physics 2022-08-11 Keisuke Nakagahara , Katsunori Wakabayashi

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 theoretically study valley-filtering in pristine graphene irradiated by bicircular counter-rotating laser drive. The dynamical symmetry of the graphene and laser drive disrupts graphene's inversion symmetry, which results distinct…

Mesoscale and Nanoscale Physics · Physics 2024-01-23 Rekha Kumari , Gopal Dixit , Arijit Kundu

Intrinsic and extrinsic valley Hall effects are predicted to emerge in graphene systems with uniform or spatially-varying mass terms. Extrinsic mechanisms, mediated by the valley-dependent scattering of electrons at the Fermi surface, can…

Mesoscale and Nanoscale Physics · Physics 2021-07-07 Fionnuala Solomon , Stephen R. Power

Valleytronics aims to control electrons in a valley-specific manner for quantum information manipulation. Due to their strong in-plane anisotropy, which enables polarization-controlled optical transitions to distinct nondegenerate valleys,…

Two-dimensional transition metal dichalcogenide (TMD) semiconductors provide a unique possibility to access the electronic valley degree of freedom using polarized light, opening the way to valley information transfer between distant…

Memory or transistor devices based on electron's spin rather than its charge degree of freedom offer certain distinct advantages and comprise a cornerstone of spintronics. Recent years have witnessed the emergence of a new field,…

Mesoscale and Nanoscale Physics · Physics 2021-09-13 Md. S. Hossain , M. K. Ma , K. A. Villegas Rosales , Y. J. Chung , L. N. Pfeiffer , K. W. West , K. W. Baldwin , M. Shayegan

We propose a device for the generation of valley polarized electronic current in bilayer graphene. By analyzing the response of this material to intense terahertz frequency light in the presence of a transverse electric field, we…

Mesoscale and Nanoscale Physics · Physics 2009-08-20 D. S. L. Abergel , Tapash Chakraborty

In monolayer transition metal dichalcogenides time-reversal symmetry, combined with space-inversion symmetry, defines the spin-valley degree of freedom. As such, engineering and control of time-reversal symmetry by optical or magnetic…

Coherent manipulation of binary degrees of freedom is at the heart of modern quantum technologies. Graphene offers two binary degrees: the electron spin and the valley. Efficient spin control has been demonstrated in many solid state…

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

The quantum geometric properties of Bloch electrons fundamentally govern light-matter interactions and optical selection rules in solids. In semiconducting transition-metal dichalcogenides, circularly polarized excitation near the band edge…