Chiral Decomposition of Twisted Graphene Multilayers with Arbitrary Stacking

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Zhang, ShengNan, Xie, Bo, Wu, QuanSheng, Liu, Jianpeng, Yazyev, Oleg V.
Format: Preprint
Published: 2020
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866913270570418176
author Zhang, ShengNan
Xie, Bo
Wu, QuanSheng
Liu, Jianpeng
Yazyev, Oleg V.
author_facet Zhang, ShengNan
Xie, Bo
Wu, QuanSheng
Liu, Jianpeng
Yazyev, Oleg V.
contents We formulate the chiral decomposition rules that govern the electronic structure of a broad family of twisted $N+M$ multilayer graphene configurations that combine arbitrary stacking order and a mutual twist. We show that at the magic angle in the chiral limit the low-energy bands of such systems are composed of chiral pseudospin doublets which are energetically entangled with two flat bands per valley induced by the moiré superlattice potential. The analytic analysis is supported by explicit numerical calculations based on realistic parameterization. We further show that applying vertical displacement fields can open up energy gaps between the pseudospin doublets and the two flat bands, such that the flat bands may carry nonzero valley Chern numbers. These results provide guidelines for the rational design of various topological and correlated states in generic twisted graphene multilayers.
format Preprint
id arxiv_https___arxiv_org_abs_2012_11964
institution arXiv
publishDate 2020
record_format arxiv
spellingShingle Chiral Decomposition of Twisted Graphene Multilayers with Arbitrary Stacking
Zhang, ShengNan
Xie, Bo
Wu, QuanSheng
Liu, Jianpeng
Yazyev, Oleg V.
Mesoscale and Nanoscale Physics
Materials Science
Strongly Correlated Electrons
We formulate the chiral decomposition rules that govern the electronic structure of a broad family of twisted $N+M$ multilayer graphene configurations that combine arbitrary stacking order and a mutual twist. We show that at the magic angle in the chiral limit the low-energy bands of such systems are composed of chiral pseudospin doublets which are energetically entangled with two flat bands per valley induced by the moiré superlattice potential. The analytic analysis is supported by explicit numerical calculations based on realistic parameterization. We further show that applying vertical displacement fields can open up energy gaps between the pseudospin doublets and the two flat bands, such that the flat bands may carry nonzero valley Chern numbers. These results provide guidelines for the rational design of various topological and correlated states in generic twisted graphene multilayers.
title Chiral Decomposition of Twisted Graphene Multilayers with Arbitrary Stacking
topic Mesoscale and Nanoscale Physics
Materials Science
Strongly Correlated Electrons
url https://arxiv.org/abs/2012.11964