Density of States and Critical Temperature in Superconductor/Ferromagnet Structures with Spin-Orbit Coupling

Abstract

We present both an analytical discussion of the weak proximity regime, and a full numerical investigation of the strong proximity regime. The results show that the spin-orbit coupling leaves a clear trace in the density of states, which displays a highly nonmonotonic behaviour as a function of magnetization directions and phase differences. We also determine how the critical temperature is affected and, interestingly, demonstrate that one can achieve a spin-valve effect using a single ferromagnet. The critical temperature is found to exhibit a highly nonmonotonic behaviour, both as a function of magnetization direction and type of spin-orbit coupling. Compared to the earlier inhomogeneously magnetized structures, this offers a new way to control the superconductivity of proximity structures.