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  • Review Article
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Reproducibility in the fabrication and physics of moiré materials

Abstract

Overlaying two atomic layers with a slight lattice mismatch or at a small rotation angle creates a moiré superlattice, which has properties that are markedly modified from (and at times entirely absent in) the ‘parent’ materials. Such moiré materials have progressed the study and engineering of strongly correlated phenomena and topological systems in reduced dimensions. The fundamental understanding of the electronic phases, such as superconductivity, requires a precise control of the challenging fabrication process, involving the rotational alignment of two atomically thin layers with an angular precision below 0.1 degrees. Here we review the essential properties of moiré materials and discuss their fabrication and physics from a reproducibility perspective.

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Fig. 1: Various factors and phenomena affecting the reproducibility of moiré materials studies.
Fig. 2: Fabrication of twisted bilayer graphene and various disorders in moiré systems.
Fig. 3: Schematics of various electronic phases and the systems in which they are observed.

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Acknowledgements

C.N.L. acknowledges support from the Department of Energy under grant number DOE DE-SC0020187. M.W.B. acknowledges support from the National Science Foundation under grant numbers DMR 2004801 and DMR-2105028. F.Z. acknowledges support from the Army Research Office under grant number W911NF-18-1-0416 and the National Science Foundation under grant numbers DMR-1945351, DMR-2105139 and DMR-1921581. K.F.M. acknowledges support from the Air Force Office of Scientific Research under award number FA9550-20-1-0219.

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C.N.L., M.W.B., K.F.M. and F.Z. discussed and co-wrote the manuscript.

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Correspondence to Chun Ning Lau.

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Lau, C.N., Bockrath, M.W., Mak, K.F. et al. Reproducibility in the fabrication and physics of moiré materials. Nature 602, 41–50 (2022). https://doi.org/10.1038/s41586-021-04173-z

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