Superconductivity induced by the inter-valley Coulomb scattering in a few layers of graphene

TL;DR

This paper investigates a purely electronic mechanism involving inter-valley Coulomb scattering as the origin of superconductivity in few-layer graphene, emphasizing the role of van Hove singularities and comparing different graphene structures.

Contribution

It introduces the inter-valley Coulomb scattering as a universal pairing mechanism for superconductivity in various few-layer graphene structures, supported by theoretical estimates matching experiments.

Findings

Superconductivity is strongly favored by van Hove singularities in the density of states.

Theoretical estimates of critical temperatures align with experimental data.

Inter-valley Coulomb scattering may be a universal pairing mechanism in few-layer graphene.

Abstract

We study the inter-valley scattering induced by the Coulomb repulsion as a purely electronic mechanism for the origin of superconductivity in few layers of graphene. The pairing is strongly favored by the presence of van Hove singularities (VHS's) in the density of states (DOS). We consider three different hetherostructures: twisted bilayer graphene (TBG), rhombohedral trilayer graphene (RTG) and Bernal bilayer graphene (BBG). We obtain trends and estimates of the superconducting (SC) critical temperature in agreement with the experimental findings, which might identify the inter-valley Coulomb scattering as a universal pairing mechanism in few layers of graphene.