Superconducting proximity effect in a diffusive ferromagnet with spin-active interfaces

We reconsider the problem of the superconducting proximity effect in a diffusive ferromagnet bounded by tunneling interfaces, using spin-dependent boundary conditions. This introduces for each interface a phase-shifting conductance G(phi) which results from the spin dependence of the phase shifts acquired by electrons upon scattering on the interface. We show that G(phi) strongly affects the density of states and supercurrents predicted for superconducting/ferromagnetic hybrid circuits. We show the relevance of this effect by identifying clear signatures of G(phi) in the data of T. Kontos [Phys. Rev. Lett. 86, 304 (2001), 89, 137007 (2002)].