Micromagnetic modeling of SOT-MRAM dynamics

We present a flexible and efficient approach to modeling the magnetization dynamics in modern SOT-MRAM cells, by coupling charge, spin, and magnetization dynamics in a three-dimensional framework. We expand on existing literature, to obtain spin current boundary conditions for modeling the Rashba-Edelstein effect. We compute the spin–orbit torques originating from both, the spin Hall and Rashba-Edelstein effect, and show that our model can reproduce experimental results for the thickness dependence of the spin torques in an Ir/CoFeB bilayer structure. Furthermore, we verify our approach by simulating magnetization reversal in field-free SOT-MRAM cells, and show that with the inclusion of the interfacial Dzyaloshinskii–Moriya interaction, we obtain domain wall motion similar to previously reported experimental results.