Spin torques in ferromagnetic/normal-metal structures

Recent theories of spin-current-induced magnetization reversal are formulated in terms of a spin-mixing conductance $G^{\mathrm{mix}}.$ We evaluate $G^{\mathrm{mix}}$ from first principles for a number of (dis)ordered interfaces between magnetic and nonmagnetic materials. We predict that the magnetization direction of a ferromagnetic insulator or of one side of a tunnel junction in a multiterminal device can be switched even though a negligible charge current is passed.