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Related papers: Space charge and screening in bilayer graphene

200 papers

Spontaneous symmetry-breaking, where the ground state of a system has lower symmetry than the underlying Hamiltonian, is ubiquitous in physics. It leads to multiply-degenerate ground states, each with a different "broken" symmetry labeled…

Mesoscale and Nanoscale Physics · Physics 2015-06-15 Jonathan S. Alden , Adam W. Tsen , Pinshane Y. Huang , Robert Hovden , Lola Brown , Jiwoong Park , David A. Muller , Paul L. McEuen

Incommensurately twisted graphene bilayers are described by long-wavelength theories, but to date such theories exist only at small angles of interlayer rotation. We construct a long wavelength theory without such a restriction, instead…

Mesoscale and Nanoscale Physics · Physics 2014-09-09 Hridis K. Pal , Steven Carter , M. Kindermann

We demonstrate that the electronic gap of a graphene bilayer can be controlled externally by applying a gate bias. From the magneto-transport data (Shubnikov-de Haas measurements of the cyclotron mass), and using a tight binding model, we…

The mechanisms of optical activity and quantum transport of twisted bilayer graphene are studied. The formation of unique electron states in the bilayer systems is studied using an effective continuum model. Such states are shown to support…

Mesoscale and Nanoscale Physics · Physics 2022-05-26 S. Ta Ho , V. Nam Do

Bilayer graphene bears an eight-fold degeneracy due to spin, valley and layer symmetry, allowing for a wealth of broken symmetry states induced by magnetic or electric fields, by strain, or even spontaneously by interaction. We study the…

Mesoscale and Nanoscale Physics · Physics 2012-02-15 F. Freitag , J. Trbovic , M. Weiss , C. Schönenberger

The specifics of charge screening and electrostatic potential spatial distribution in multilayered graphene films placed in between charged substrates is theoretically analyzed. It is shown that by varying the areal charge densities on the…

Mesoscale and Nanoscale Physics · Physics 2014-03-21 Natalya A. Zimbovskaya , Eugene J. Mele

Coherent motion of the electrons in the Bloch states is one of the fundamental concepts of the charge conduction in solid state physics. In layered materials, however, such a condition often breaks down for the interlayer conduction, when…

Mesoscale and Nanoscale Physics · Physics 2015-06-05 Youngwook Kim , Hoyeol Yun , Seung-Geol Nam , Minhyeok Son , Dong Su Lee , Dong Chul Kim , S. Seo , Hee Cheul Choi , Hu-Jong Lee , Sang Wook Lee , Jun Sung Kim

Ballistic, gate-defined devices in two-dimensional materials offer a platform for electron optics phenomena influenced by the material's properties and gate control. We study the ray trajectory dynamics of all-electronic, gate-defined…

Mesoscale and Nanoscale Physics · Physics 2024-03-18 Lukas Seemann , Angelika Knothe , Martina Hentschel

We analyze the range of validity of Thomas Fermi theory for describing charge density modulations induced by external potentials in neutral graphene. We compare exact results obtained from a tight-binding calculation with those of linear…

Mesoscale and Nanoscale Physics · Physics 2010-09-07 L. Brey , H. A. Fertig

We investigate the electronic density redistribution of rotated bilayer graphene under a perpendicular electric field, showing that the layers are actually coupled even for large angles. This layer-layer coupling is evidenced by the charge…

Mesoscale and Nanoscale Physics · Physics 2012-03-26 E. Suárez Morell , P. Vargas , L. Chico , L. Brey

Bilayer graphene is normally a semimetal with parabolic dispersion, but a tunable bandgap up to few hundreds meV can be opened by breaking the symmetry between the layers through an external potential. Ab-initio calculations show that the…

Mesoscale and Nanoscale Physics · Physics 2015-09-30 Simone De Liberato

Graphene [1] and its bilayer have generated tremendous excitement in the physics community due to their unique electronic properties [2]. The intrinsic physics of these materials, however, is partially masked by disorder, which can arise…

Mesoscale and Nanoscale Physics · Physics 2010-09-10 Benjamin E. Feldman , Jens Martin , Amir Yacoby

We introduce effective field theories for the electronic properties of graphene in terms of relativistic fermions propagating in 2+1 dimensions, and outline how strong inter-electron interactions may be modelled by numerical simulation of a…

Strongly Correlated Electrons · Physics 2015-01-09 Simon Hands , Wes Armour , Costas Strouthos

The electronic structure of the zig-zag bilayer strip is analyzed. The electronic spectra of the bilayer strip is computed. The dependence of the edge state band flatness on the bilayer width is found. The density of states at the Fermi…

Materials Science · Physics 2015-06-04 M. Pudlak , R. Pincak

Motivated by recent experimental results we calculate from first-principles the lifetime of low-energy quasiparticles in bilayer graphene (BLG). We take into account the scattering rate arising from electron-electron interactions within the…

Mesoscale and Nanoscale Physics · Physics 2023-09-11 Catalin D. Spataru , François Léonard

Semiconductor double-layers in the quantum Hall regime tend to have superfluid exciton condensate ground states when the total filling factor is an odd integer, provided that the Landau orbitals at the Fermi level in the two layers have the…

Strongly Correlated Electrons · Physics 2019-03-07 Ming Xie , Allan H. MacDonald

We predict that neutral graphene bilayers are pseudospin magnets in which the charge density-contribution from each valley and spin spontaneously shifts to one of the two layers. The band structure of this system is characterized by a…

Strongly Correlated Electrons · Physics 2008-01-18 Hongki Min , Giovanni Borghi , Marco Polini , A. H. MacDonald

Proximity effects resulting from depositing a graphene layer on a TMD substrate layer change the dynamics of the electronic states in graphene, inducing spin orbit coupling (SOC) and staggered potential effects. An effective Hamiltonian…

Mesoscale and Nanoscale Physics · Physics 2016-12-21 Abdulrhman M. Alsharari , Mahmoud M. Asmar , Sergio E. Ulloa

We extensively investigate the electronic and transport properties of a twisted bilayer graphene when subjected to both an external perpendicular electric field and a magnetic field. Using a basic tight-binding model, we show the flat…

Mesoscale and Nanoscale Physics · Physics 2023-11-13 Priyanka Sinha , Ayan Mondal , Simão Meneses João , Bheema Lingam Chittari

Twisted bilayer graphene is a rich condensed matter system, which allows one to tune energy scales and electronic correlations. The low-energy physics of the resulting moir\'e structure can be mathematically described in terms of a…

Mesoscale and Nanoscale Physics · Physics 2024-06-21 Alireza Parhizkar , Victor Galitski