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arXiv · 1803.08057

Topological Superconductivity in Twisted Multilayer Graphene

Cenke Xu·Leon Balents
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Abstract

We study a minimal Hubbard model for electronically driven superconductivity in a correlated flat mini-band resulting from the superlattice modulation of a twisted graphene multilayer. The valley degree of freedom drastically modifies the nature of thepreferred pairing states, favoring spin triplet $d+id$ order with a valley singlet structure. We identify two candidates in this class, which are both topological superconductors. These states support half-vortices carrying half the usual superconducting flux quantum $hc/(4e)$, and have topologically protected gapless edge states.

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Cenke Xu, Leon Balents. 2018-03-21. Topological Superconductivity in Twisted Multilayer Graphene. https://doi.org/10.1103/physrevlett.121.087001

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