Glenn Wagner

Zurich University, Switzerland

13 Jun 2023 Tue 5 pm

                                      IBS Center for Theoretical Physics of Complex Systems (PCS), Administrative Office (B349), Theory Wing, 3rd floor

                                      Expo-ro 55, Yuseong-gu, Daejeon, South Korea, 34126 Tel: +82-42-878-8633                     

A striking series of experiments have observed superconductivity in Bernal-stacked bilayer graphene under conditions where the energy bands are flattened by applying an electrical displacement field. Intriguingly, the superconductor only appears at  non-zero magnetic fields, or in settings when spin-orbit coupling is induced by coupling to a substrate. We present a functional renormalization group study of superconductivity in Bernal graphene that provides a unified explanation for the superconducting mechanism in both cases. We identify a purely electronic instability of the Kohn-Luttinger type, which can be triggered either by magnetic fields or Ising spin-orbit coupling, naturally explaining the behaviour seen in experiments.

  1. superconductivity from repulsive interactions in bernal bilayer