Extended s–d models for the dynamics of noncollinear magnetization: Short review of two different approaches

Abstract In the literature there are two s–d models (by De Angeli et al. and by Zhang and Zhang) on the dynamics of noncollinear magnetization which treat the spin current density in completely different ways. It is shown that both models yield similar results for the spatial dependence of the damping term in such systems. The interrelations between the two models are discussed extensively.