Interplay between magnetization dynamics and spin transport

For transition-metal based ferromagnets, magnetic and spin transport properties are intimately correlated. By using an exchange interaction between conduction electrons and nonuniform magnetization vectors, we show that many spin-dependent phenomena in the nonequilibrium conditions can be understood in a unified picture. In particular, we discuss the generation of nonequilibrium spin density and spin current induced by domain wall motion. These induced spin density and spin currents produce an electromotive force, a domain wall resistance, inter-band electronic transitions between two spin channels, and an enhanced spatial-dependence of damping. As examples, we apply our formulations to study domain wall dynamics and corresponding induced charge currents or voltage.