Band structure determines the motion of electrons in a solid, giving rise to exotic phenomena when properly engineered. Drawing an analogy between electrons and photons, artificially designed optical lattices indicate the possibility of a similar band modulation effect in graphene systems. Yet due to the fermionic nature of electrons, modulated electronic systems promise far richer categories of behaviors than those found in optical lattices. Here, we uncovered a strong modulation of electronic states in bilayer graphene subject to periodic potentials. We observed for the first time the hybridization of electron and hole sub-bands, resulting in local band gaps at both primary and secondary charge neutrality points. Such hybridization leads to the formation of flat bands, enabling the study of correlated effects in graphene systems. This work may provide a novel way to manipulate electronic states in layered systems, which is important to both fundamental research and application.
|Original language||English (US)|
|Number of pages||6|
|Journal||National Science Review|
|State||Published - Dec 19 2019|
Bibliographical noteKAUST Repository Item: Exported on 2022-06-14
Acknowledged KAUST grant number(s): OSR-2016-CRG5-2996
Acknowledgements: S.W., M.Z., S.Y., Y.W. and X.Z. acknowledge the support from the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Materials Sciences and Engineering Division within the van der Waals Heterostructures Program (KCWF16) under contract No. DEAC02-05-CH11231 for sample preparation, the support from the National Science Foundation (NSF) MRI grant 1725335 for low-temperature measurement, and the support from the King Abdullah University of Science and Technology (KAUST) Office of Sponsored Research award OSR-2016-CRG5-2996 for sample fabrication. C.Z. and J.H. acknowledge the support from NSF EFMA-1741660. K.W. and T.T. acknowledge the support from the Elemental Strategy Initiative conducted by the Ministry of Education, Culture, Sports, Science and Technology (MEXT), Japan, and CREST (JPMJCR15F3), Japan Science and Technology Agency (JST).
This publication acknowledges KAUST support, but has no KAUST affiliated authors.
ASJC Scopus subject areas