Model of spin accumulation and spin torque in spatially varying magnetisation structures: limitations of the micromagnetic approach

作者：Chureemart P^*; D'Amico I; Chantrell R W

来源：Journal of Physics: Condensed Matter , 2015, 27(14): 146004.

DOI：10.1088/0953-8984/27/14/146004

• spin-transfer torque
• spin accumulation model
• atomistic modelling

We study the spin-transfer torque acting on the magnetisation when injecting polarised conduction electrons into a magnetic system. The spin accumulation is calculated self-consistently and naturally includes the adiabatic and non-adiabatic contributions which depend on the rate of change of magnetisation in relation to the spin diffusion length. As an example we consider a system where a spin-polarised current is injected into a structure containing a domain wall. We calculate the spin torque and related parameters corresponding to the adiabatic and non-adiabatic terms directly from the spin accumulation, and find that the dynamic micromagnetic approach based on adiabatic and non-adiabatic terms with constant coefficients is valid only for systems with slowly spatially varying magnetisation.

• 出版日期2015-4-15