Spin-transport in multi-terminal normal metal - ferromagnet systems with non-collinear magnetizations

A theory of spin-transport in hybrid normal metal ferromagnetic electronic circuits is developed, taking into account non-collinear spin-accumulation. Spin-transport through resistive elements is described by 4 conductance parameters. Microscopic expression for these conductances are derived in terms of scattering matrices and explicitly calculated for simple models. The circuit theory is applied to 2-terminal and 3-terminal devices attached to ferromagnetic reservoirs. PACS. 72.10.Bg General formulation of transport theory – 72.10.-d Theory of electronic transport; scattering mechanisms – 75.50.-i Magnetic films and multilayers – 75.70.Pa Giant magnetoresistance