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Related papers: Excitonic effects in twisted bilayer graphene

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Inter-Landau-level transitions in the bilayer graphene at high perpendicular magnetic field at the filling-factor v<<1 have been studied. The next-nearest-neighbor transitions, energy difference between dimer and non-dimer sites and layer…

Mesoscale and Nanoscale Physics · Physics 2015-05-27 V. E. Bisti , N. N. Kirova

Utilizing the established Bistritzer-MacDonald model for twisted bilayer graphene (tBLG), we theoretically investigate the non-Hermitian (NH) topological properties of this in the presence of non-reciprocal (NR) hopping on both layers and…

Mesoscale and Nanoscale Physics · Physics 2025-10-14 Kamalesh Bera , Debasish Mondal , Arijit Saha , Debashree Chowdhury

We consider magnetic breakdown in twisted bilayer graphene where electrons may hop between semiclassical $k$-space trajectories in different layers. These trajectories within a doubled Brillouin zone constitute a network in which an…

Mesoscale and Nanoscale Physics · Physics 2014-02-11 Chi-Ken Lu , H. A. Fertig

An unconventional insulating phase and a superconducting phase were recently discovered in the twisted bilayer graphene [Y. Cao et al, Nature {\bf 556}, 80; {\bf 556}, 43 (2018)], but the relevant low-energy electronic states have not been…

Mesoscale and Nanoscale Physics · Physics 2019-05-02 Long Zhang

Excitons in bilayer transition metal dichalcogenides (2L-TMDs) are Coulomb-bound electron/hole pairs that can be viewed as broadly tunable analogs of atomic or molecular systems. Here, we study the properties of 2L-TMD excitons under strong…

Mesoscale and Nanoscale Physics · Physics 2023-03-20 S. Kovalchuk , K. Greben , A. Kumar , S. Pessel , K. Watanabe , T. Taniguchi , D. Christiansen , M. Selig , A. Knorr , K. I. Bolotin

We investigate the twist-angle and gate dependence of the proximity exchange coupling in twisted graphene on monolayer Cr$_2$Ge$_2$Te$_6$ from first principles. The proximitized Dirac band dispersions of graphene are fitted to a model…

Mesoscale and Nanoscale Physics · Physics 2022-03-21 Klaus Zollner , Jaroslav Fabian

The electronic properties of twisted bilayer graphene (TBG) can be dramatically different from those of a single graphene layer, in particular when the two layers are rotated relative to each other by a small angle. TBG has recently…

We develop a two stage renormalization group which connects the continuum Hamiltonian for twisted bilayer graphene at length scales shorter than the moire superlattice period to the Hamiltonian for the active narrow bands only which is…

Strongly Correlated Electrons · Physics 2020-12-21 Oskar Vafek , Jian Kang

Gated heterostructures containing bilayer graphene with staggered sublattice potentials are investigated by tight binding model with Rashba spin-orbital coupling and Hubbard interaction. The topological phase diagrams depend on the…

Mesoscale and Nanoscale Physics · Physics 2018-09-05 Ma Luo , Zhibing Li

A study of correlation effects in twisted bilayer graphene, using the extended coupled cluster method, is presented. This approach considers both self-consistent mean-field and beyond mean-field contributions, and can describe phase…

Strongly Correlated Electrons · Physics 2026-03-20 Ingvars Vitenburgs , Niels R. Walet

Twisted bilayer graphene (TBG) exhibits flat electronic bands at the so-called magic angle ($\sim 1.1^\circ$), leading to strong electron correlations and emergent quantum phases such as superconductivity and correlated insulating states.…

Mesoscale and Nanoscale Physics · Physics 2025-04-01 Ayan Mondal , Priyanka Sinha , Bheema Lingam Chittari

We find exact analytic expressions for the energies and wavefunctions of the charged and neutral excitations above the exact ground states (at rational filling per unit cell) of projected Coulomb Hamiltonians in twisted bilayer graphene.…

Strongly Correlated Electrons · Physics 2022-04-29 B. Andrei Bernevig , Biao Lian , Aditya Cowsik , Fang Xie , Nicolas Regnault , Zhi-Da Song

Twisted bilayer graphene (tBLG) has emerged as an exciting platform for novel condensed matter physics. However, electron-phonon ($e$-ph) interactions in tBLG and their effects on electronic transport are not completely understood. Here we…

Materials Science · Physics 2024-03-01 Shiyuan Gao , Jin-Jian Zhou , Yao Luo , Marco Bernardi

We introduce twisted trilayer graphene (tTLG) with two independent twist angles as an ideal system for the precise tuning of the electronic interlayer coupling to maximize the effect of correlated behaviors. As established by experiment and…

Mesoscale and Nanoscale Physics · Physics 2020-10-12 Ziyan Zhu , Stephen Carr , Daniel Massatt , Mitchell Luskin , Efthimios Kaxiras

Using resonant 2-photon excitation of interlayer electrons in twisted bilayer graphene (tBLG), we resolve photoluminescence (PL) that tunes spectrally with stacking angle, {\theta}. This weak signal is 4- 5$\times$ larger than the…

Mesoscale and Nanoscale Physics · Physics 2019-04-01 Hiral Patel , Lujie Huang , Cheol-Joo Kim , Jiwoong Park , Matt W. Graham

We derive the explicit Hamiltonian of twisted bilayer graphene (TBG) with Coulomb interaction projected into the flat bands, and study the symmetries of the Hamiltonian. First, we show that all projected TBG Hamiltonians can be written as…

Strongly Correlated Electrons · Physics 2022-04-29 B. Andrei Bernevig , Zhi-Da Song , Nicolas Regnault , Biao Lian

The effect of the intersite and interplane Coulomb interactions between the Dirac fermions on the formation of the Kohn-Luttinger superconductivity in bilayer doped graphene is studied disregarding the effects of the van der Waals potential…

Superconductivity · Physics 2016-02-08 M. Yu. Kagan , V. A. Mitskan , M. M. Korovushkin

Twisted graphene bilayers show a complex electronic structure, further modified by interaction effects. The main features can be obtained from effective models, which make use a few phenomenological parameters. We analyze the influence of…

Strongly Correlated Electrons · Physics 2019-03-04 Niels R. Walet , Francisco Guinea

Excitons in monolayer transition-metal dichalcogenides (TMDs) have garnered significant attention because of their large binding energies due to weakly screened Coulomb interaction, and direct bandgap at the K/K$^\prime$ point in the…

Flatbands with extremely narrow bandwidths on the order of a few mili-electron volts can appear in twisted multilayer graphene systems for appropriate system parameters. Here we investigate the electronic structure of a twisted bi-bilayer…

Mesoscale and Nanoscale Physics · Physics 2019-06-24 Narasimha Raju Chebrolu , Bheema Lingam Chittari , Jeil Jung