Abstract

We perform a random phase approximation (RPA) calculation for a spin-valley polarized model of rhombohedral tetra-layer graphene to study chiral superconductivity from the Kohn-Luttinger mechanism. Using a realistic band structure and form factors, we solve the superconducting self-consistency equation numerically and find p+ip pairing near the Van Hove singularity, with a Chern-number change from C = -1 to C = 0 as displacement field increases. The optimal Cooper-pair momentum is generically finite, leading to an incommensurate Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) superconducting state. At low temperature the spectrum is often fully gapped, while near Tc Bogoliubov Fermi surfaces can emerge.

Abstract

We perform a random phase approximation (RPA) calculation for a spin-valley polarized model of rhombohedral tetra-layer graphene to study chiral superconductivity from the Kohn-Luttinger mechanism. Using a realistic band structure and form factors, we solve the superconducting self-consistency equation numerically and find p+ip pairing near the Van Hove singularity, with a Chern-number change from C = -1 to C = 0 as displacement field increases. The optimal Cooper-pair momentum is generically finite, leading to an incommensurate Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) superconducting state. At low temperature the spectrum is often fully gapped, while near Tc Bogoliubov Fermi surfaces can emerge.

Abstract

We perform a random phase approximation (RPA) calculation for a spin-valley polarized model of rhombohedral tetra-layer graphene to study chiral superconductivity from the Kohn-Luttinger mechanism. Using a realistic band structure and form factors, we solve the superconducting self-consistency equation numerically and find p+ip pairing near the Van Hove singularity, with a Chern-number change from C = -1 to C = 0 as displacement field increases. The optimal Cooper-pair momentum is generically finite, leading to an incommensurate Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) superconducting state. At low temperature the spectrum is often fully gapped, while near Tc Bogoliubov Fermi surfaces can emerge.

Abstract

We perform a random phase approximation (RPA) calculation for a spin-valley polarized model of rhombohedral tetra-layer graphene to study chiral superconductivity from the Kohn-Luttinger mechanism. Using a realistic band structure and form factors, we solve the superconducting self-consistency equation numerically and find p+ip pairing near the Van Hove singularity, with a Chern-number change from C = -1 to C = 0 as displacement field increases. The optimal Cooper-pair momentum is generically finite, leading to an incommensurate Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) superconducting state. At low temperature the spectrum is often fully gapped, while near Tc Bogoliubov Fermi surfaces can emerge.