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arXiv · 2307.04605

Moire-enabled topological superconductivity in twisted bilayer graphene

Maryam Khosravian·Elena Bascones·Jose L. Lado
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Abstract

Twisted van der Waals materials have risen as highly tunable platform for realizing unconventional superconductivity. Here we demonstrate how a topological superconducting state can be driven in a twisted graphene multilayer at a twist angle of approximately 1.6 degrees proximitized to other 2D materials. We show that an encapsulated twisted bilayer subject to induced Rashba spin-orbit coupling, s-wave superconductivity and exchange field generates a topological superconducting state enabled by the moire pattern. We demonstrate a variety of topological states with different Chern numbers highly tunable through doping, strain and bias voltage. Our proposal does not depend on a fine tuning of the twist angle, but solely on the emergence of moire minibands and is applicable for twist angles between 1.3 and 3 degrees. Our results establish the potential of twisted graphene bilayers to create artificial topological superconductivity without requiring ultraflat dispersions.

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Maryam Khosravian, Elena Bascones, Jose L. Lado. 2023-07-10. Moire-enabled topological superconductivity in twisted bilayer graphene. https://doi.org/10.1088/2053-1583%2Fad3b0c

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