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Related papers: Valley separation via trigonal warping

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We describe an angularly asymmetric interface-scattering mechanism which allows to spatially separate the electrons in the two low-energy valleys of bilayer graphene. The effect occurs at electrostatically defined interfaces separating…

Mesoscale and Nanoscale Physics · Physics 2010-11-05 Henning Schomerus

We study the electronic transport properties at the intersection of three topological zero-lines as the elementary current partition node that arises in minimally twisted bilayer graphene. Unlike the partition laws of two intersecting…

Mesoscale and Nanoscale Physics · Physics 2020-09-02 Tao Hou , Yafei Ren , Yujie Quan , Jeil Jung , Wei Ren , Zhenhua Qiao

Bilayer graphene (two coupled graphitic monolayers arranged according to Bernal stacking) is a two-dimensional gapless semiconductor with a peculiar electronic spectrum different from the Dirac spectrum in the monolayer material. In…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 K. Kechedzhi , Vladimir I. Fal'ko , E. McCann , B. L. Altshuler

A two-dimensional electron system placed in a magnetic field develops Landau levels, where strong Coulomb interactions lead to the appearance of many-body correlated ground states. Quantum numbers similar to the electron spin enable the…

Mesoscale and Nanoscale Physics · Physics 2023-08-14 Ke Huang , Hailong Fu , Danielle Reifsnyder Hickey , Nasim Alem , Xi Lin , Kenji Watanabe , Takashi Taniguchi , Jun Zhu

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

Theory predicts that the application of an electric field breaks the inversion symmetry of AB and BA stacked domains in twisted bilayer graphene, resulting in the formation of a triangular network of one-dimensional valley-protected helical…

Mesoscale and Nanoscale Physics · Physics 2021-09-10 J. D. Verbakel , Q. Yao , K. Sotthewes , H. J. W. Zandvliet

Spatial division multiplexing utilizes the directionality of lights propagating k-vector to separate it into distinct spatial directions. Here we show that the anisotropy of orthogonal spatial Solitons propagating in a single Graphene…

Mesoscale and Nanoscale Physics · Physics 2017-04-05 Jonathan K. George , Volker J. Sorger

In this letter we study the valley degeneracy splitting of the transition-metal dichalcogenides monolayer by first-principles calculations. The local magnetic moments are introduced into the system when the transition-metal atoms are…

Materials Science · Physics 2016-09-06 Xiaofang Chen , Liangshuai Zhong , Xiao Li , Jingshan Qi

We have studied the interplay of valley polarization and the Coulomb interaction on the energy spectrum, persistent current, and optical absorption of a graphene quantum ring. We show that the interaction has a dramatic effect on the nature…

Mesoscale and Nanoscale Physics · Physics 2008-06-18 D. S. L. Abergel , Vadim M. Apalkov , Tapash Chakraborty

We investigate interaction-induced valley domain walls in bilayer graphene in the $\nu=0$ quantum Hall state, subject to a perpendicular electric field that is antisymmetric across a line in the sample. Such a state can be realized in a…

Strongly Correlated Electrons · Physics 2012-05-10 Chia-Wei Huang , Efrat Shimshoni , H. A. Fertig

We describe a simple setup generating pure valley currents -- valley transport without charge transport -- in strained graphene nanoribbons with zigzag edges. The crucial ingredient is a uniaxial strain pattern which couples to the…

Mesoscale and Nanoscale Physics · Physics 2020-02-28 Étienne Lantagne-Hurtubise , Xiao-Xiao Zhang , Marcel Franz

The electrostatic confinement of massless charge carriers is hampered by Klein tunneling. Circumventing this problem in graphene mainly relies on carving out nanostructures or applying electric displacement fields to open a band gap in…

In graphene, the valleys represent spin-like quantities and can act as a physical resource in valley-based electronics to novel quantum computation schemes. Here we demonstrate a direct route to tune and read the valley quantum states of…

Mesoscale and Nanoscale Physics · Physics 2012-06-19 Atindra Nath Pal , Vidya Kochat , Arindam Ghosh

Using the valley degree of freedom as a carrier of information for storage and processing, valley polarization plays a crucial role. A variety of mechanisms for valley polarization have been proposed, among which the valley-layer coupling…

Materials Science · Physics 2025-05-29 San-Dong Guo , Liguo Zhang , Xiao-Shu Guo , Gangqiang Zhu

Electronic properties of surface areas decoupled from graphite are studied using scanning tunnelling microscopy and spectroscopy. We show that it is possible to identify decoupled graphene monolayer, Bernal bilayer, and Bernal trilayer on…

Mesoscale and Nanoscale Physics · Physics 2015-03-06 Long-Jing Yin , Si-Yu Li , Jia-Bin Qiao , Jia-Cai Nie , Lin He

We describe the weak localization correction to conductivity in ultra-thin graphene films, taking into account disorder scattering and the influence of trigonal warping of the Fermi surface. A possible manifestation of the chiral nature of…

Mesoscale and Nanoscale Physics · Physics 2009-03-12 K. Kechedzhi , E. McCann , Vladimir I. Fal'ko , H. Suzuura , T. Ando , B. L. Altshuler

The valleys of two-dimensional transition metal dichalcogenides (TMDCs) offer a new degree of freedom for information processing. To take advantage of this valley degree of freedom, on one hand, it is feasible to control valleys by…

Manipulating the valley degree of freedom to encode information for potential valleytronic devices has ignited a new direction in solid-state physics. A significant, fundamental challenge in the field of valleytronics is how to generate and…

Mesoscale and Nanoscale Physics · Physics 2020-07-02 Hui-Ying Mu , Yi-Tong Yao , Jie-Ru Li , Guo-Cai Liu , Chao He , Ying-Jie Sun , Guang Yang , Xing-Tao An , Yong-Zhe Zhang , Jian-Jun Liu

The rise of graphene opens a new door to qubit implementation, as discussed in the recent proposal of valley pair qubits in double quantum dots of gapped graphene (Wu et al., arXiv: 1104.0443 [cond-mat.mes-hall]). The work here presents the…

Mesoscale and Nanoscale Physics · Physics 2011-07-05 G. Y. Wu , N. -Y. Lue , L. Chang

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