English
Related papers

Related papers: Giant Interaction-Induced Gap and Electronic Phase…

200 papers

Twisted bilayer graphene (TBG) provides a unique framework to elucidate the interplay between strong correlations and topological phenomena in two-dimensional systems. The existence of multiple electronic degrees of freedom -- charge, spin,…

Strongly Correlated Electrons · Physics 2021-01-27 Yuan Da Liao , Jian Kang , Clara N. Breiø , Xiao Yan Xu , Han-Qing Wu , Brian M. Andersen , Rafael M. Fernandes , Zi Yang Meng

When layers of graphene are rotationally misaligned by the magic angle, the moir\'e superlattice features extremely flat bands. Due to the enhanced density of states, the Coulomb interaction induces a variety of instabilities. The most…

Atomically thin materials offer multiple opportunities for layer-by-layer control of their electronic properties. While monolayer graphene (MLG) is a zero-gap system, Bernal-stacked bilayer graphene (BLG) acquires a finite band gap when the…

We derive the Hamiltonian for trilayer moir\'e systems with the Coulomb interaction projected onto the bands near the charge neutrality point. Motivated by the latest experimental results, we focus on the twisted symmetric trilayer graphene…

Strongly Correlated Electrons · Physics 2021-05-19 Dumitru Călugăru , Fang Xie , Zhi-Da Song , Biao Lian , Nicolas Regnault , B. Andrei Bernevig

Motivated by the recent discoveries of superconductivity in bilayer and trilayer graphene, we theoretically investigate superconductivity and other interaction-driven phases in multilayer graphene stacks. To this end, we study the density…

Superconductivity · Physics 2023-03-06 Areg Ghazaryan , Tobias Holder , Erez Berg , Maksym Serbyn

Twisted bilayer graphene near the magic angle is known to have a cascade of insulating phases at integer filling factors of the low-energy bands. In this Letter we address the nature of these phases through an unrestricted, large-scale…

Strongly Correlated Electrons · Physics 2024-09-30 Khagendra Adhikari , Kangjun Seo , K. S. D. Beach , Bruno Uchoa

We study the symmetries of twisted trilayer graphene's band structure under various extrinsic perturbations, and analyze the role of long-range electron-electron interactions near the first magic angle. The electronic structure is modified…

Mesoscale and Nanoscale Physics · Physics 2021-10-04 Vo Tien Phong , Pierre A. Pantaleón , Tommaso Cea , Francisco Guinea

The Hamiltonian of the magic-angle twisted symmetric trilayer graphene (TSTG) can be decomposed into a TBG-like flat band Hamiltonian and a high-velocity Dirac fermion Hamiltonian. We use Hartree-Fock mean field approach to study the…

Mesoscale and Nanoscale Physics · Physics 2021-10-19 Fang Xie , Nicolas Regnault , Dumitru Călugăru , B. Andrei Bernevig , Biao Lian

Recently, fractional quantum anomalous Hall effects have been discovered in two-dimensional moir\'{e} materials when a topologically nontrivial band with Chern number $\mathcal{C}=1$ is partially doped. Remarkably, superlattice Bloch bands…

Mesoscale and Nanoscale Physics · Physics 2025-07-30 Vo Tien Phong , Cyprian Lewandowski

The non-interacting energy spectrum of graphene and its bilayer counterpart consists of multiple degeneracies owing to the inherent spin, valley and layer symmetries. Interactions among charge carriers are expected to spontaneously break…

Mesoscale and Nanoscale Physics · Physics 2015-05-20 R. Thomas Weitz , Monica T. Allen , Benjamin E. Feldman , Jens Martin , Amir Yacoby

Two monolayers of graphene twisted by a small `magic' angle exhibit nearly flat bands leading to correlated electronic states and superconductivity, whose precise nature including possible broken symmetries, remain under debate. Here we…

Strongly Correlated Electrons · Physics 2019-12-13 Jong Yeon Lee , Eslam Khalaf , Shang Liu , Xiaomeng Liu , Zeyu Hao , Philip Kim , Ashvin Vishwanath

We theoretically calculate the interaction-induced frictional Coulomb drag resistivity between two graphene monolayers as well as between two graphene bilayers, which are spatially separated by a distance "$d$". We show that the drag…

Mesoscale and Nanoscale Physics · Physics 2011-12-23 E. H. Hwang , Rajdeep Sensarma , S. Das Sarma

Nontrivial interacting phases can emerge in elementary materials. As a prime example, continuing advances in device quality have facilitated the observation of a variety of spontaneous quantum Hall-like states, a cascade of Stoner-like…

Mesoscale and Nanoscale Physics · Physics 2024-08-30 Felix Winterer , Fabian R. Geisenhof , Noelia Fernandez , Anna M. Seiler , Fan Zhang , R. Thomas Weitz

For the unconventional superconducting phases in moire materials, a critical question is the role played by electronic interactions in the formation of Cooper pairs. In twisted bilayer graphene (tBLG), the strength of electronic…

We report on the results of the first-principle numerical study of spontaneous breaking of chiral (sublattice) symmetry in suspended monolayer graphene due to electrostatic interaction, which takes into account the screening of Coulomb…

Strongly Correlated Electrons · Physics 2015-06-15 M. V. Ulybyshev , P. V. Buividovich , M. I. Katsnelson , M. I. Polikarpov

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

The tunable band structure and nontrivial topology of multilayer rhombohedral graphene lead to a variety of correlated electronic states with isospin orders-meaning ordered states in the combined spin and valley degrees of freedom-dictated…

We investigate the electronic structure of the flat bands induced by moir\'e superlattices and electric fields in nearly aligned ABC trilayer graphene-boron nitride interfaces where Coulomb effects can lead to correlated gapped phases. Our…

Mesoscale and Nanoscale Physics · Physics 2019-01-09 Bheema Lingam Chittari , Guorui Chen , Yuanbo Zhang , Feng Wang , Jeil Jung

We study the Coulomb drag between two single graphene sheets in intrinsic and extrinsic graphene systems with no interlayer tunneling. The general expression for the nonlinear susceptibility appropriate for single-layer graphene systems is…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 Wang-Kong Tse , Ben Yu-Kuang Hu , S. Das Sarma

ABA-stacked trilayer graphene (TLG), the simplest system consisting of both massless and massive Dirac fermions, is expected to exhibit many interesting broken-symmetry quantum Hall states and interaction-induced phenomena. However,…

Materials Science · Physics 2018-07-25 Yu Zhang , Jia-Bin Qiao , Long-Jing Yin , Lin He