Superconductivity and Charge Density Wave in Twisted Bilayer Graphene
Published 2018-05-16Version 1
We study electronic ordering instabilities of twisted bilayer graphene with two electrons per supercell, where correlated insulator state and superconductivity are recently observed. Motivated by the Fermi surface nesting and the proximity to Van Hove singularity, we introduce a hot-spot model to study the effect of various electron interactions systematically. Using renormalization group method, we find intertwined spin-singlet (triplet) superconducting and charge (spin) density-wave orders, consistent with the experimental observation of resistivity changing from metallic to insulating and finally to superconducting behavior upon decreasing temperature.