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arXiv · 2405.14661

Tuning monolayer superconductivity in twisted NbSe$_2$ graphene heterostructures

Shun Asano·Youichi Yanase
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Abstract

The recent advent of artificial structures has triggered the emergence of fascinating phenomena that could not exist in natural compounds. A prime example is twisted multilayers, i.e., moir\'e superlattices represented by magic-angle twisted bilayer graphene (MATBG). As in the case of MATBG, unconventional band hybridization can induce a new type of superconductivity: artificial band engineering by twist induces properties different from the original systems. Here, we apply this perspective to a monolayer superconductor NbSe$_2$ stacked with a twist on doped graphene. We show that the superconducting states of the NbSe$_2$ layer change dramatically by varying the twist angle. Our result shows that twist tuning, in addition to substrate effects, will provide a strategy for designing monolayer superconductors with high controllability.

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Shun Asano, Youichi Yanase. 2024-05-23. Tuning monolayer superconductivity in twisted NbSe$_2$ graphene heterostructures. https://doi.org/10.1103/physrevb.110.134516

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