Non-equilibrium quantum transport and analytical conductance formula in spin-textured diffusive superconducting heterostructures

We study non-equilibrium quantum transport of spin, heat, and charge in diffusive heterostructures including both superconductors and materials with spin-dependent fields, such as textured ferromagnets and spin-orbit coupled materials. Using the quasiclassical theory of superconductivity, we derive a general analytical formula for the zero-temperature charge conductance valid in the non-linear regime. The analytical results are in excellent agreement with previous numerical calculations at small but finite temperatures. We predict a strong deviation between the conductance spectra and local density of states in certain junctions, which is important to correctly identify spectroscopic fingerprints of unconventional superconductivity.