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Title: Interacting twisted bilayer graphene with systematic modeling of structural relaxation
Abstract Twisted bilayer graphene (TBG) has drawn significant interest due to recent experiments which show that TBG can exhibit strongly correlated behavior such as the superconducting and correlated insulator phases. Much of the theoretical work on TBG has been based on analysis of the Bistritzer–MacDonald model which includes a phenomenological parameter to account for lattice relaxation. In this work, we use a newly developed continuum model which systematically accounts for the effects of structural relaxation. In particular, we model structural relaxation by coupling linear elasticity to a stacking energy that penalizes disregistry. We compare the impact of the two relaxation models on the corresponding many-body model by defining an interacting model projected to the flat bands. We perform tests at charge neutrality at both the Hartree–Fock and coupled cluster singles and doubles level of theory and find the systematic relaxation model gives quantitative differences from the simplified relaxation model.  more » « less
Award ID(s):
2406981
PAR ID:
10633882
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
IOP Publishing Ltd
Date Published:
Journal Name:
Electronic Structure
Volume:
7
Issue:
3
ISSN:
2516-1075
Page Range / eLocation ID:
035001
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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