Spin polarization of quasiparticle states in S/F structures with a finite transparency of the SF interface

The proximity effect between a massive superconductor (S) and a mesoscopic layer of a normal ferromagnetic metal (F) is investigated for arbitrary tra nsparency of the SF interface and arbitrary value of the proximity effect. For the case of high transparency of the SF interface and a low value of th e proximity effect, the spatial distribution of the order parameter in the S layer and the densities of quasiparticle states at the interface for the S and F layers are found analytically as functions of the exchange field. I t is shown that in mesoscopic S/F structures the single-particle excitation s are polarized in both the F and S metals. (C) 2000 American Institute of Physics. [S1063-777X(00)00602-2].