p-wave superconductivity near a transverse saturation field

TL;DR

This paper explores how p-wave superconductivity in URhGe is enhanced near a transverse saturation field, revealing two domes in the transition temperature and the role of soft magnons in mediating pairing.

Contribution

It provides a theoretical analysis of reentrant superconductivity and the behavior of T_{sc} under transverse magnetic fields in an Ising ferromagnetic superconductor.

Findings

Two domes in T_{sc} as a function of h_x

Strong enhancement of T_{sc} near the saturation field h_s

Superconductivity with zero-spin pairs due to field cancellation

Abstract

We investigate reentrant superconductivity in an Ising ferromagnetic superconductor URhGe under a transverse magnetic field h_x. The superconducting transition temperature for p-wave order parameters T_{sc} is calculated and shows two domes as a function of h_x. We find strong enhancement of T_{sc} in the high-field dome near a saturation field h_s where the spins align in the transverse direction. Soft magnons generate strong attractive interactions there. Spin components of the pairing show a significant change between h_x<h_s and h_x>h_s. We also discuss the appearance of superconductivity with zero-spin pair due to cancellation between external and exchange fields.