The Origin of Magic Angle in Twisted Bilayer Graphene is Heisenberg’s Uncertainty Principle
- 15 September 2021
- journal article
- research article
- Published by American Chemical Society (ACS) in The Journal of Physical Chemistry Letters
- Vol. 12 (37), 9124-9131
- https://doi.org/10.1021/acs.jpclett.1c02486
Abstract
The magic-angle twisted bilayer graphene (MATBG) recently attracted intensive research attention because of its fascinating and unconventional electronic properties. Herein, we claim the magic-angle phenomenon originates from the Heisenberg uncertainty principle, which can provide intensive explanations on finite size effect and twist-dependent low energy band variations. We showed that flat bands could exist only near the AA stacking structure rather than AB. The finite-size effect gives the minimal size of graphene quantum dots (R ≳ 4 nm) for the emergence of the Dirac point, and the uncertainty relation provides the upper bound for moiré supercells (R ≲ 23.5 nm) in twisted bilayer graphene, which is the quantum mechanical boundary for the emergence of flat bands. Combining the twist dependence of moiré supercell size, we proved that there is only one possible magic angle in MATBG at θ ≈ 1.1°. Our result implies that the unconventional phenomena in MATBG originate from the fundamental feature of condensed matter physics.Funding Information
- National Natural Science Foundation of China (21805234, 22075240)
- Guangdong Introducing Innovative and Entrepreneurial Teams (2019ZT08L101)
- Shenzhen Institute of Artificial Intelligence and Robotics for Society
- Shenzhen Fundamental Research Foundation (JCYJ20180508162801893)
This publication has 23 references indexed in Scilit:
- π–π stacking between polyaromatic hydrocarbon sheets beyond dispersion interactionsPhysical Chemistry Chemical Physics, 2016
- Detection of interlayer interaction in few-layer graphenePhysical Review B, 2015
- Moiré bands in twisted double-layer grapheneProceedings of the National Academy of Sciences of the United States of America, 2011
- Determination of the gate-tunable band gap and tight-binding parameters in bilayer graphene using infrared spectroscopyPhysical Review B, 2009
- Buckle or breakNature Materials, 2007
- Intrinsic ripples in grapheneNature Materials, 2007
- Noncovalent Interactions between Graphene Sheets and in Multishell (Hyper)FullerenesThe Journal of Physical Chemistry C, 2007
- Interlayer cohesive energy of graphite from thermal desorption of polyaromatic hydrocarbonsPhysical Review B, 2004
- Tata Lectures on Theta IPublished by Springer Science and Business Media LLC ,1983
- Intercalation compounds of graphiteAdvances in Physics, 1981