Imperial College London
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ProfessorJohannesLischner

Faculty of Engineering, Department of Materials

Professor of Theory and Simulation of Materials
 
 
 
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Contact

 

+44 (0)20 7594 9949j.lischner

 
 
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Location

 

342Bessemer BuildingSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Liang:2020:10.1103/physrevb.102.155146,
author = {Liang, X and Goodwin, ZAH and Vitale, V and Corsetti, F and Mostofi, AA and Lischner, J},
doi = {10.1103/physrevb.102.155146},
journal = {Physical Review B},
pages = {155146  1--155146  12},
title = {Effect of bilayer stacking on the atomic and electronic structure of twisted double bilayer graphene},
url = {http://dx.doi.org/10.1103/physrevb.102.155146},
volume = {102},
year = {2020}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - Twisted double bilayer graphene has recently emerged as an interesting moiré material that exhibits strong correlation phenomena that are tunable by an applied electric field. Here we study the atomic and electronic properties of three different graphene double bilayers: double bilayers composed of two AB stacked bilayers (AB/AB), double bilayers composed of two AA stacked bilayers (AA/AA), as well as heterosystems composed of one AB and one AA bilayer (AB/AA). The atomic structure is determined using classical force fields. We find that the inner layers of the double bilayer exhibit significant in-plane and out-of-plane relaxations, similar to twisted bilayer graphene. The relaxations of the outer layers depend on the stacking: atoms in AB bilayers follow the relaxations of the inner layers, while atoms in AA bilayers attempt to avoid higher-energy AA stacking. For the relaxed structures, we calculate the electronic band structures using the tight-binding method. All double bilayers exhibit flat bands at small twist angles, but the shape of the bands depends sensitively on the stacking of the outer layers. To gain further insight, we study the evolution of the band structure as the outer layers are rigidly moved away from the inner layers, while preserving their atomic relaxations. This reveals that the hybridization with the outer layers results in an additional flattening of the inner-layer flat band manifold. Our results establish AA/AA and AB/AA twisted double bilayers as interesting moiré materials with different flat band physics compared to the widely studied AB/AB system.
AU  - Liang,X
AU  - Goodwin,ZAH
AU  - Vitale,V
AU  - Corsetti,F
AU  - Mostofi,AA
AU  - Lischner,J
DO  - 10.1103/physrevb.102.155146
EP  - 1
PY  - 2020///
SN  - 2469-9950
SP  - 155146
TI  - Effect of bilayer stacking on the atomic and electronic structure of twisted double bilayer graphene
T2  - Physical Review B
UR  - http://dx.doi.org/10.1103/physrevb.102.155146
UR  - https://journals.aps.org/prb/abstract/10.1103/PhysRevB.102.155146
UR  - http://hdl.handle.net/10044/1/84539
VL  - 102
ER  -
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