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arXiv · 2306.09799

One-Dimensional Moir\'e Physics and Chemistry in Heterostrained Bilayer Graphene

Gabriel R. Schleder·Michele Pizzochero·Efthimios Kaxiras
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Abstract

Twisted bilayer graphene (tBLG) has emerged as a promising platform to explore exotic electronic phases. However, the formation of moir\'e patterns in tBLG has thus far been confined to the introduction of twist angles between the layers. Here, we propose heterostrained bilayer graphene (hBLG), as an alternative avenue to access twist-angle-free moir\'e physics via lattice mismatch. Using atomistic and first-principles calculations, we demonstrate that uniaxial heterostrain can promote isolated flat electronic bands around the Fermi level. Furthermore, the heterostrain-induced out-of-plane lattice relaxation may lead to a spatially modulated reactivity of the surface layer, paving the way for the moir\'e-driven chemistry and magnetism. We anticipate that our findings can be readily generalized to other layered materials.

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Gabriel R. Schleder, Michele Pizzochero, Efthimios Kaxiras. 2023-06-16. One-Dimensional Moir\'e Physics and Chemistry in Heterostrained Bilayer Graphene. https://doi.org/10.1021/acs.jpclett.3c01919

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