English
Related papers

Related papers: Space charge and screening in bilayer graphene

200 papers

Charge carriers in bilayer graphene occupy two parabolic continua of electron-like and hole-like states which differ by the alignment between carrier pseudospin and its momentum, the property known as chirality. Due to chirality…

Mesoscale and Nanoscale Physics · Physics 2015-06-10 A. V. Shytov

We propose an implementation of a valley selective electronic Veselago lens in bilayer graphene. We demonstrate that in the presence of an appropriately oriented potential step, low-energy electrons radiating from a point source can be…

Mesoscale and Nanoscale Physics · Physics 2012-06-26 Csaba G. Péterfalvi , László Oroszlány , Colin J. Lambert , József Cserti

We theoretically investigate optical injection processes, including one- and two-photon carrier injection and two-color coherent current injection, in twisted bilayer graphene with moderate angles. The electronic states are described by a…

Mesoscale and Nanoscale Physics · Physics 2022-02-16 Ze Zheng , Ying Song , Yu Wei Shan , Wei Xin , Jin Luo Cheng

We develop a microscopic theory of a strong electromagnetic field interaction with gated bilayer graphene. Quantum kinetic equations for density matrix are obtained using a tight binding approach within second quantized Hamiltonian in an…

Mesoscale and Nanoscale Physics · Physics 2017-05-24 A. A. Avetisyan , A. P. Djotyan , K. Moulopoulos

In a quantizing magnetic field, the chiral two-dimensional electron gas in Landau level $N=0$ of bilayer graphene goes through a series of phase transitions at integer filling factors $\nu \in \left[ -3,3\right] $ when the strength of an…

Mesoscale and Nanoscale Physics · Physics 2015-10-28 R. Côté , Manuel Barrette , Élie Bouffard

At the classical level, two-dimensional dilaton gravity coupled to an abelian gauge field has charged black hole solutions, which have much in common with four-dimensional Reissner-Nordstrom black holes, including multiple asymptotic…

High Energy Physics - Theory · Physics 2009-11-11 Andrei V. Frolov , Kristjan R. Kristjansson , Larus Thorlacius

The chiral Hamiltonian for twisted graphene bilayers is written as a $2\times2$ matrix operator by a renormalization of the Hamiltonian that takes into account the particle-hole symmetry. This results in an effective Hamiltonian with an…

Mesoscale and Nanoscale Physics · Physics 2023-08-01 Gerardo G. Naumis , Leonardo A. Navarro-Labastida , Enrique Aguilar-Méndez , Abdiel Espinosa-Champo

When a bilayer of graphene is placed in a suitably configured field effect device, an asymmetry gap can be generated and the carrier concentration made different in each layer. This provides a tunable semiconducting gap, and the valence and…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 E. J. Nicol , J. P. Carbotte

The orbital magnetism in spatially varying magnetic fields is studied in monolayer graphene within the effective mass approximation. We find that, unlike the conventional two-dimensional electron system, graphene with small Fermi wave…

Mesoscale and Nanoscale Physics · Physics 2015-05-13 Mikito Koshino , Yasunori Arimura , Tsuneya Ando

An extraordinary low vacuum barrier height of 2.30 eV has been found on the zigzag-edge of graphene terminated with the secondary amine via the ab initio calculation. This edge structure has a flat band of edge states attached to the gamma…

Materials Science · Physics 2012-09-05 Weiliang Wang , Zhibing Li

In a magnetic field bilayer graphene supports an octet of zero-energy Landau levels with an extra twofold degeneracy in Landau orbitals n=0 and n=1. It is shown that this orbital degeneracy is lifted due to Coulombic quantum fluctuations of…

Mesoscale and Nanoscale Physics · Physics 2012-10-25 K. Shizuya

Bilayer graphene is a highly tunable material: not only can one tune the Fermi energy using standard gates, as in single-layer graphene, but the band structure can also be modified by external perturbations such as transverse electric…

We study electronic, charge, and magnetic properties of twisted bilayer graphene with fillings $2\leq n\leq 6$ per moire unit cell within the recently introduced formulation of extended dynamical mean-field theory (E-DMFT) for…

Strongly Correlated Electrons · Physics 2022-09-30 A. A. Katanin

We study ballistic transport in periodically gated bilayer graphene as a candidate for a 2D electronic metamaterial. Our calculations use the equilibrium Green function formalism and take into account quantum corrections to charge density…

Mesoscale and Nanoscale Physics · Physics 2020-03-18 Xianqing Lin , David Tomanek

We report experimental and theoretical evidence that GaGeTe is a basic $Z_2$ topological semimetal with three types of charge carriers: bulk-originated electrons and holes as well as surface state electrons. This electronic situation is…

We compare the main feature of the measured Raman scattering spectra from single layer graphene with a bilayer in which the two layers are arbitrarily misoriented. The profiles of the 2D bands are very similar having only one component,…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 Philippe Poncharal , Anthony Ayari , Thierry Michel , Jean-Louis Sauvajol

We construct a Wannier basis for twisted bilayer graphene that is projected only from the Bloch functions of the twisted bilayer flat bands. The $C_3$ and $C_{2} \mathcal{T}$ symmetries act locally on the Wannier functions while the Wannier…

Mesoscale and Nanoscale Physics · Physics 2022-10-25 Jiawei Zang , Jie Wang , Antoine Georges , Jennifer Cano , Andrew J. Millis

Graphene is a two-dimensional Dirac semimetal showing interesting properties as a result of its dispersion relation with both quasiparticles and quasiholes or matter and anti-matter. We introduce a topological nodal ring semimetal in…

Mesoscale and Nanoscale Physics · Physics 2023-05-03 Karyn Le Hur , Sariah Al Saati

The recently realized bilayer graphene system with a twist angle of $30^\circ$ offers a new type of quasicrystal which unites the dodecagonal quasicrystalline nature and graphene's relativistic properties. Here, we introduce a concise…

Mesoscale and Nanoscale Physics · Physics 2019-05-10 Pilkyung Moon , Mikito Koshino , Young-Woo Son

Theoretical calculations show that twisted double bilayer graphene (TDBG) under a transverse electric field develops a valley Chern number 2 at charge neutrality. Using thermodynamic and thermal activation measurements we report the…

Mesoscale and Nanoscale Physics · Physics 2024-12-10 Yimeng Wang , G. William Burg , Biao Lian , Kenji Watanabe , Takashi Taniguchi , B. Andrei Bernevig , Emanuel Tutuc