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Related papers: Minimal Geometry for Valley Filtering in Graphene

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Graphene is a very promising test-bed for the field of electron quantum optics. However, a fully tunable and coherent electronic beam splitter is still missing. We report the demonstration of electronic beam splitters in graphene that…

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

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

A valley filter capable of generating a valley-polarized current is a crucial element in valleytronics, yet its implementation remains challenging. Here, we propose a valley filter made of a graphene bilayer which exhibits a 1D moir\'{e}…

Mesoscale and Nanoscale Physics · Physics 2024-04-19 Kai Shao , Hao Geng , Erfu Liu , Jose L. Lado , Wei Chen , D. Y. Xing

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 propose a geometric phase-resolved tunneling valley Hall effect based on the coherent transmission through two combined electric barriers in $\alpha-\mathcal{T}_3$ lattices. It is shown that the backreflected electrons at the barrier…

Mesoscale and Nanoscale Physics · Physics 2024-11-07 W. Zeng

We investigate the electronic confinement in bilayer graphene by topological loops of different shapes. These loops are created by lateral gates acting via gap inversion on the two graphene sheets. For large-area loops the spectrum is well…

Mesoscale and Nanoscale Physics · Physics 2022-01-12 Nassima Benchtaber , David Sánchez , Llorenç Serra

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

Electrons in two-dimensional hexagonal materials have valley degree of freedom, which can be used to encode and process quantum information. The valley-selective excitations, governed by the circularly polarised light resonant with the…

Mesoscale and Nanoscale Physics · Physics 2021-03-19 M. S. Mrudul , Álvaro Jiménez-Galán , Misha Ivanov , Gopal Dixit

We propose a simple, yet highly efficient and robust device for producing valley polarized current in graphene. The device comprises of two distinct components; a region of uniform uniaxial strain, adjacent to an out-of-plane magnetic…

Mesoscale and Nanoscale Physics · Physics 2010-08-06 T. Fujita , M. B. A. Jalil , S. G. Tan

We study spatial symmetry in general ABA-stacked multilayer graphene to illustrate how electronic spectra at the two valleys are related in a magnetic field. We show that the lattice of multilayers with an even number of layers, as well as…

Mesoscale and Nanoscale Physics · Physics 2015-05-14 Mikito Koshino , Edward McCann

Developing alternative paradigms of electronics beyond silicon technology requires the exploration of fundamentally new physical mechanisms, such as the valley specific phenomena in hexagonal two-dimensional materials. We realize ballistic…

Mesoscale and Nanoscale Physics · Physics 2018-12-11 Jing Li , Rui-Xing Zhang , Zhenxi Yin , Jianxiao Zhang , Kenji Watanabe , Takashi Taniguchi , Chaoxing Liu , Jun Zhu

The interaction between electrons in graphene under high magnetic fields drives the formation of a rich set of quantum Hall ferromagnetic phases (QHFM), with broken spin or valley symmetry. Visualizing atomic scale electronic wavefunctions…

Mesoscale and Nanoscale Physics · Physics 2022-02-02 Xiaomeng Liu , Gelareh Farahi , Cheng-Li Chiu , Zlatko Papic , Kenji Watanabe , Takashi Taniguchi , Michael P. Zaletel , Ali Yazdani

We report the finding of the analogous valley Hall effect in phononic systems arising from mirror symmetry breaking, in addition to spatial inversion symmetry breaking. We study topological phases of plates and spring-mass models in Kagome…

Mesoscale and Nanoscale Physics · Physics 2019-04-17 Natalia Lera , Daniel Torrent , Pablo San-Jose , Johan Christensen , Jose Vicente Alvarez

A unique feature of the complex band structures of moir\'e materials is the presence of minivalleys, their hybridization, and scattering between them. Here we investigate magneto-transport oscillations caused by scattering between…

The existence of nontrivial Berry phases associated with two inequivalent valleys in graphene provides interesting opportunities for investigating the valley-projected topological states. Examples of such studies include observation of…

Mesoscale and Nanoscale Physics · Physics 2020-05-13 C. -C. Hsu , M. L. Teague , J. -Q. Wang , N. -C. Yeh

The valley Hall effect arises from valley contrasting Berry curvature and requires inversion symmetry breaking. Here, we propose a nonlinear mechanism to generate a valley Hall current in systems with both inversion and time-reversal…

Mesoscale and Nanoscale Physics · Physics 2025-01-28 Kamal Das , Koushik Ghorai , Dimitrie Culcer , Amit Agarwal

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 develop a theory of Coulomb interaction-related contribution to the photogalvanic current of the carriers of charge in two-dimensional non-centrosymmetric Dirac materials possessing a nontrivial structure of valleys and exposed to an…

Mesoscale and Nanoscale Physics · Physics 2024-06-13 V. M. Kovalev , A. V. Parafilo , O. V. Kibis , I. G. Savenko

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