Current-Induced Motion of Narrow Domain Walls and Dissipation in Ferromagnetic Metals

Abstract

Spin transport equations in a non-homogeneous ferromagnet are derived in the limit where the sd exchange coupling between the electrons in the conduction band and those in the d band is dominant. It is shown that spin diffusion in ferromagnets assumes a tensor form. The diagonal terms are renormalized with respect to that in normal metals and enhances the dissipation in the magnetic system while the off-diagonal terms renormalize the precessional frequency of the conduction electrons and enhances the non-adiabatic spin torque. To demonstrate the new physics in our theory, we show that self-consistent solutions of the spin diffusion equations and the Landau-Lifshitz equations in the presence of a current lead to a an increase in the terminal velocity of a domain wall which becomes strongly dependent on its width. We also provide a simplified equation that predicts damping due to the conduction electrons.

References in corpus (9)

• Roles of non-equilibrium conduction electrons on magnetization dynamics of ferromagnets
• Micromagnetic understanding of current-driven domain wall motion in patterned nanowires
• Real-space observation of current-driven domain wall motion in submicron magnetic wires
• Theory of Current-Driven Domain Wall Motion: A Poorman's Approach
• Current-spin coupling for ferromagnetic domain walls in fine wires
• Current-induced magnetization dynamics in disordered itinerant ferromagnets
• Thermally-Assisted Current-Driven Domain Wall Motion
• Angular dependence of domain wall resistivity in artificial magnetic domain structures
• Analysis Of Measured Transport Properties Of Domain Walls In Magnetic Nanowires And Films