Transport in ferromagnet/superconductor spin valves

We consider charge transport properties in realistic, fabricable, ferromagnet/superconductor spin valves having a layered structure F1/N/F2/S, where F1 and F2 denote the ferromagnets, S the superconductor, and N the normal-metal spacer usually inserted in actual devices. Our calculation is fully self-consistent, as required to ensure that conservation laws are satisfied. We include the effects of scattering at all the interfaces. We obtain results for the device conductance G, as a function of bias voltage, for all values of the angle φ between the magnetizations of the F1 and F2 layers and a range of realistic values for the material and geometrical parameters in the sample. We discuss, in the context of our results for G, the relative influence of all parameters on the spin valve properties. We also study the spin current and the corresponding spin-transfer torque in F1/F2/S structures.