Pair density wave and reentrant superconducting tendencies originating from valley polarization

We investigate superconducting pairing tendencies of a two-dimensional electron fluid with both valley and spin degrees of freedom, both without and in the presence of an in-plane magnetic field. We present suggestive theoretical arguments that spontaneous valley polarization can lead to exotic singlet superconducting tendencies, including pair density wave order at zero field and reentrant superconductivity at high field. We also find a reduced magnetic response in the polarized valley, which allows a finite violation of the Pauli limit. These results are obtained by a mean-field approach to a generalized t-J model on a triangular lattice and in the dilute limit. Phenomenological similarities to results of recent magic-angle twisted trilayer graphene experiments are noted.

Automated summary

This study investigates the superconducting pairing tendencies of a two-dimensional electron fluid with both valley and spin degrees of freedom. The results suggest that spontaneous valley polarization can lead to exotic superconducting tendencies, including pair density wave order at zero field and reentrant superconductivity at high field.