Tuning monolayer superconductivity in twisted NbSe$_2$ graphene heterostructures

TL;DR

This paper demonstrates that twisting monolayer NbSe$_2$ on doped graphene significantly alters its superconducting properties, offering a new method for designing tunable 2D superconductors through twist engineering.

Contribution

It introduces the concept of twist angle control in monolayer NbSe$_2$ heterostructures to modulate superconductivity, expanding the scope of moiré engineering beyond bilayer systems.

Findings

Superconducting states vary with twist angle.

Twist tuning offers high controllability of superconductivity.

Potential for designing customizable 2D superconductors.

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.