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Related papers: Space charge and screening in bilayer graphene

200 papers

Because graphene is an atomically two-dimensional gapless semiconductor with nearly identical conduction and valence bands, graphene-based bilayers are attractive candidates for high-temperature electron-hole pair condensation. We present…

Mesoscale and Nanoscale Physics · Physics 2008-09-04 Hongki Min , Rafi Bistritzer , Jung-Jung Su , A. H. MacDonald

We study the influence of the quantum geometry on the magnetic responses of quadratic band crossing semimetals. More explicitly, we examine the Landau levels, quantum Hall effect, and magnetic susceptibility of a general two-band…

Mesoscale and Nanoscale Physics · Physics 2024-11-18 Chang-geun Oh , Jun-Won Rhim , Bohm-Jung Yang

We study the possibility of Wigner crystallization in both single- and and bi-layer graphene using a real space tight binding model. In addition to verifying our earlier prediction for single layer graphene, we predict that the bilayer…

Strongly Correlated Electrons · Physics 2007-06-13 Hari P. Dahal , Tim O. Wehling , Kevin S. Bedell , Jian-Xin Zhu , A. V. Balatsky

We construct a minimal theory describing the optical activity of a thin sheet of a twisted material, the simplest example of which is twisted bilayer graphene. We introduce the notion of "twisted electrical conductivity", which parametrizes…

Mesoscale and Nanoscale Physics · Physics 2020-08-10 Dung Xuan Nguyen , Dam Thanh Son

We consider graphene bilayer in a constant magnetic field of arbitrary orientation (i.e. tilted with respect to the graphene plane). In the low energy approximation to tight binding model with Peierls substitution, we find the exact…

Mesoscale and Nanoscale Physics · Physics 2010-08-04 Young-Hwan Hyun , Yoonbai Kim , Corneliu Sochichiu , Min-Young Choi

The low energy electronic spectra of rotationally faulted graphene bilayers are studied using a long wavelength theory applicable to general commensurate fault angles. Lattice commensuration requires low energy electronic coherence across a…

Mesoscale and Nanoscale Physics · Physics 2015-05-18 E. J. Mele

The nematic phase transition in electronic liquids, driven by Coulomb interactions, represents a new class of strongly correlated electronic ground states. We studied suspended samples of bilayer graphene, annealed so that it achieves very…

We present simple models to describe the in-plane and the out-of-plane lattice relaxation in twisted bilayer and symmetrically twisted trilayer graphene. Analytical results and series expansions show that for twist angles {\theta} > 1…

Mesoscale and Nanoscale Physics · Physics 2023-11-28 Adrián Ceferino , Francisco Guinea

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

There are known two distinct types of the integer quantum Hall effect. One is the conventional quantum Hall effect, characteristic of two-dimensional semiconductor systems, and the other is its relativistic counterpart recently observed in…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 K. S. Novoselov , E. McCann , S. V. Morozov , V. I. Falko , M. I. Katsnelson , U. Zeitler , D. Jiang , F. Schedin , A. K. Geim

We have investigated the effects of inplane and interplane nearest neighbour overlap integrals ($s_0$ and $s_1$) and site energy difference between atoms in two different sublattices in the same graphene layer ($\Delta$) on the electronic…

Materials Science · Physics 2009-07-27 Rupali Kundu

We present a framework for understanding the recently observed cascade transitions and the Landau level degeneracies at every integer filling of twisted bilayer graphene. The Coulomb interaction projected onto narrow bands causes the…

Strongly Correlated Electrons · Physics 2022-01-05 Jian Kang , B. Andrei Bernevig , Oskar Vafek

Among the variety of correlated states exhibited by twisted bilayer graphene, cascades in the spectroscopic properties and in the electronic compressibility occur over larger ranges of energy, twist angle and temperature compared to other…

Strongly Correlated Electrons · Physics 2023-08-29 Anushree Datta , M. J. Calderón , A. Camjayi , E. Bascones

We investigate the contribution of the low-energy electronic excitations towards the Raman spectrum of bilayer graphene for the incoming photon energy Omega >> 1eV. Starting with the four-band tight-binding model, we derive an effective…

Mesoscale and Nanoscale Physics · Physics 2010-08-17 M. Mucha-Kruczynski , O. Kashuba , V. I. Fal'ko

We examine the coexisting spin and charge density waves as a possible ground state of the magic-angle twisted bilayer graphene. When interactions are not included, the spectrum of the material has 4 (8 if spin is taken into account) almost…

Strongly Correlated Electrons · Physics 2023-04-24 A. O. Sboychakov , A. V. Rozhkov , A. L. Rakhmanov

We argue that at finite carrier density and large displacement fields, bilayer graphene is prone to $\ell =0$ and $\ell = 1$ Pomeranchuk Fermi surface instabilities. The broken symmetries are driven by non-local exchange interactions which…

Mesoscale and Nanoscale Physics · Physics 2015-07-08 Jeil Jung , Marco Polini , Allan H. MacDonald

The flat bands in bilayer graphene(BLG) are sensitive to electric fields E\bot directed between the layers, and magnify the electron-electron interaction effects, thus making BLG an attractive platform for new two-dimensional (2D) electron…

Mesoscale and Nanoscale Physics · Physics 2012-03-23 J. Velasco , L. Jing , W. Bao , Y. Lee , P. Kratz , V. Aji , M. Bockrath , C. N. Lau , C. Varma , R. Stillwell , D. Smirnov , Fan Zhang , J. Jung , A. H. MacDonald

The transport properties of a bilayer graphene are studied theoretically within a self-consistent Born approximation. The electronic spectrum is composed of $k$-linear dispersion in the low-energy region and $k$-square dispersion as in an…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Mikito Koshino , Tsuneya Ando

The one-loop polarization function of graphene has been calculated at zero temperature for arbitrary wavevector, frequency, chemical potential (doping), and band gap. The result is expressed in terms of elementary functions and is used to…

Strongly Correlated Electrons · Physics 2008-12-12 P. K. Pyatkovskiy

The electronic properties of doped bilayer graphene in presence of bottom and top gates have been studied and characterized by means of Density Functional Theory calculations. Varying independently the bottom and top gates it is possible to…

Materials Science · Physics 2015-05-13 Paola Gava , Michele Lazzeri , A. Marco Saitta , Francesco Mauri