Role of non-collinear polarizer layer in spin transfer torque switching processes

摘要

We recently reported that spin transfer torque switching current density is very sensitive to the junction sizes and the exchange stiffness constants of the free layer, based on micromagnetic simulations. The results are very complicated and far from the simple macro-spin model because of the non-coherent spin switching processes. The dependence of switching current density on junction sizes and the exchange stiffness constants becomes systematic when we employ the non-collinear polarizer layer. We found that the non-collinear polarizer layer enhances the coherency of the spin dynamics by breaking symmetric spin configurations and causes noticeable reductions in the switching current density.