Transport in ferromagnetic/superconducting heterostructures*

We consider the transport theory in nano-scale ferromagnetic/superconducting heterostructures with multiple ferromagnetic layers. We do so using fully self consistent, numerical methods in the clean limit. Many properties unique to these systems arise due to the proximity effects between ferromagnets and superconductors. We determine the conductance in each spin channel and analyze its dependence on the magnetic misalignment angle between the ferromagnets, as well as on other physical parameters pertinent to multi-layered systems. We quantitatively describe some of these properties and we discuss our results in connection to proposed experiments.