Abstract

Recent experiments have reported chiral time-reversal broken superconductivity in n-layer rhombohedral graphene for n = 4, 5, 6. Introducing a moiré potential by alignment with a hexagonal boron nitride substrate suppresses the superconductivity but leads instead to various fractional quantum anomalous Hall phenomena. Motivated by these observations, we consider the fate of the phase transition between a chiral Landau Fermi liquid metal and a composite Fermi liquid metal in the presence of attractive interactions. We show that generically the Landau Fermi liquid close to the transition to the composite Fermi liquid is stable against superconductivity, so the evolution between the composite Fermi liquid and chiral superconductor goes through an intermediate stable Landau Fermi liquid phase for weak attractive interactions. With stronger interactions, the evolution can instead go through a non-Abelian paired quantum Hall state.

Abstract

Recent experiments have reported chiral time-reversal broken superconductivity in n-layer rhombohedral graphene for n = 4, 5, 6. Introducing a moiré potential by alignment with a hexagonal boron nitride substrate suppresses the superconductivity but leads instead to various fractional quantum anomalous Hall phenomena. Motivated by these observations, we consider the fate of the phase transition between a chiral Landau Fermi liquid metal and a composite Fermi liquid metal in the presence of attractive interactions. We show that generically the Landau Fermi liquid close to the transition to the composite Fermi liquid is stable against superconductivity, so the evolution between the composite Fermi liquid and chiral superconductor goes through an intermediate stable Landau Fermi liquid phase for weak attractive interactions. With stronger interactions, the evolution can instead go through a non-Abelian paired quantum Hall state.

Abstract

Recent experiments have reported chiral time-reversal broken superconductivity in n-layer rhombohedral graphene for n = 4, 5, 6. Introducing a moiré potential by alignment with a hexagonal boron nitride substrate suppresses the superconductivity but leads instead to various fractional quantum anomalous Hall phenomena. Motivated by these observations, we consider the fate of the phase transition between a chiral Landau Fermi liquid metal and a composite Fermi liquid metal in the presence of attractive interactions. We show that generically the Landau Fermi liquid close to the transition to the composite Fermi liquid is stable against superconductivity, so the evolution between the composite Fermi liquid and chiral superconductor goes through an intermediate stable Landau Fermi liquid phase for weak attractive interactions. With stronger interactions, the evolution can instead go through a non-Abelian paired quantum Hall state.

Abstract

Recent experiments have reported chiral time-reversal broken superconductivity in n-layer rhombohedral graphene for n = 4, 5, 6. Introducing a moiré potential by alignment with a hexagonal boron nitride substrate suppresses the superconductivity but leads instead to various fractional quantum anomalous Hall phenomena. Motivated by these observations, we consider the fate of the phase transition between a chiral Landau Fermi liquid metal and a composite Fermi liquid metal in the presence of attractive interactions. We show that generically the Landau Fermi liquid close to the transition to the composite Fermi liquid is stable against superconductivity, so the evolution between the composite Fermi liquid and chiral superconductor goes through an intermediate stable Landau Fermi liquid phase for weak attractive interactions. With stronger interactions, the evolution can instead go through a non-Abelian paired quantum Hall state.