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Related papers: Magnetic field-tunable valley-contrasting pseudoma…

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We examine strain-induced quantized Landau levels in graphene. Specifically, arc-bend strains are found to cause nonuniform pseudomagnetic fields. Using an effective Dirac model which describes the low-energy physics around the nodal…

Mesoscale and Nanoscale Physics · Physics 2012-09-05 Yichen Chang , Tameem Albash , Stephan Haas

The massless Dirac fermions and the ease to introduce spatial and magnetic confinement in graphene provide us unprecedented opportunity to explore confined relativistic matter in this condensed-matter system. Here we report the interplay…

Mesoscale and Nanoscale Physics · Physics 2024-03-08 Ya-Ning Ren , Qiang Cheng , Chao Yan , Ke Lv , Mo-Han Zhang , Qing-Feng Sun , Lin He

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 show that in bilayer graphene it is possible to achieve a very restrictive confinement of the massless Dirac fermions zero-modes by using inhomogeneous magnetic fields. Specifically, we show that, using a suitable nonuniform magnetic…

Mesoscale and Nanoscale Physics · Physics 2018-11-13 Lucas Sourrouille

Magic angle twisted bilayer graphene has emerged as a powerful platform for studying strongly correlated electron physics, owing to its almost dispersionless low-energy bands and the ability to tune the band filling by electrostatic gating.…

Mesoscale and Nanoscale Physics · Physics 2021-07-21 Nikhil Tilak , Xinyuan Lai , Shuang Wu , Zhenyuan Zhang , Mingyu Xu , Raquel de Almeida Ribeiro , Paul C Canfield , Eva Y. Andrei

Both topological crystalline insulators surfaces and graphene host multi-valley massless Dirac fermions which are not pinned to a high-symmetry point of the Brillouin zone. Strain couples to the low-energy electrons as a time-reversal…

Strongly Correlated Electrons · Physics 2016-05-18 Jörn W. F. Venderbos , Liang Fu

Realizations of some topological phases in two-dimensional systems rely on the challenge of jointly incorporating spin-orbit and magnetic exchange interactions. Here, we predict the formation and control of a fully valley-polarized quantum…

Mesoscale and Nanoscale Physics · Physics 2021-10-25 Marc Vila , Jose H. Garcia , Stephan Roche

A system in a quantum superposition of distinct states usually exhibits many peculiar behaviors. Here we show that putting quasiparticles of graphene into superpositions of states in the two valleys can complete change the properties of the…

Mesoscale and Nanoscale Physics · Physics 2014-08-25 Jia-Bin Qiao , Zhao-Dong Chu , Liang-Mei Wu , Lin He

The magnetic field dependence of energy levels in gapped single- and bilayer graphene quantum dots (QDs) defined by electrostatic gates is studied analytically in terms of the Dirac equation. Due to the absence of sharp edges in these types…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 Patrik Recher , Johan Nilsson , Guido Burkard , Bjoern Trauzettel

Magnetic confinement in graphene has been of recent and growing interest because its potential applications in nanotechnology. In particular, the observation of the so called magnetic edge states in graphene has opened the possibility to…

Mesoscale and Nanoscale Physics · Physics 2010-08-31 Gabriela Murguia

We investigate electric and magnetic properties of graphene with rotationally symmetric strain. The strain generates large pseudo magnetic field with alternating sign in space, which forms a strongly confined quantum dot connected to six…

Mesoscale and Nanoscale Physics · Physics 2013-05-29 Kyung-Joong Kim , Yaroslav Blanter , Kang-Hun Ahn

We study the confinement of Dirac fermions in graphene and in carbon nanotubes by an external magnetic field, mechanical deformations or inhomogeneities in the substrate. By applying variational principles to the square of the Dirac…

Mesoscale and Nanoscale Physics · Physics 2015-01-08 Vit Jakubsky , David Krejcirik

In contrast to recent description [Phys. Rev. Lett. 106 (2011)116803], we show that pseudo spin in graphene is not completely a real angular momentum. The pseudo spin only in the direction perpendicular to graphene sheet is real angular…

Mesoscale and Nanoscale Physics · Physics 2014-09-12 Bumned Soodchomshom

We investigate physical properties that can be used to distinguish the valley degree of freedom in systems where inversion symmetry is broken, using graphene systems as examples. We show that the pseudospin associated with the valley index…

Materials Science · Physics 2011-11-10 Di Xiao , Wang Yao , Qian Niu

In this Letter, both the manipulation of valley-polarized currents and the optical-like behaviors of Dirac fermions are theoretically explored in polycrystalline graphene. When strain is applied, the misorientation between two graphene…

Mesoscale and Nanoscale Physics · Physics 2016-12-14 Viet Hung Nguyen , Samuel Dechamps , Philippe Dollfus , Jean-Christophe Charlier

We study graphene with an adsorbed spin texture, where the localized spins create a periodic magnetic flux. The latter produces gaps in the graphene spectrum and breaks the valley symmetry. The resulting effective electronic model, which is…

Materials Science · Physics 2011-03-31 Antonio Hill , Andreas Sinner , Klaus Ziegler

Unlike regular electron spin, the pseudospin degeneracy of Fermi points in graphene does not couple directly to magnetic field. Therefore, graphene provides a natural vehicle to observe the integral and fractional quantum Hall physics in an…

Strongly Correlated Electrons · Physics 2009-11-11 Csaba Toke , Paul E. Lammert , Jainendra K. Jain , Vincent H. Crespi

The aim of this work is to describe the electronic properties of graphene in a constant magnetic field in the long wavelength approximation with random binary disorder, by solving the Soven equation self-consistently. Density of state…

Mesoscale and Nanoscale Physics · Physics 2015-03-03 Juan Sebastian Ardenghi , Pablo Bechthold , Estela Gonzalez , Paula Jasen , Alfredo Juan

Flat electronic bands with tunable structures offer opportunities for the exploitation and manipulation of exotic interacting quantum states. Here, we present a controllable route to construct easily tunable flat bands in folded graphene,…

Graphene is a unique two-dimensional material with rich new physics and great promise for applications in electronic devices. Physical phenomena such as the half-integer quantum Hall effect and high carrier mobility are critically dependent…