Spin Hall Switching Enabled by Uniaxial In-Plane Magnetocrystalline Anisotropy

In this work, we examine spin-orbit-torque magnetic random-access-memory (SOT-MRAM) devices stabilized by in-plane uniaxial magnetocrystalline anisotropy, enabling switching without shape constraints or external fields. We investigate the interaction between uniaxial in-plane anisotropy and the spin-Hall effect in this device – an interaction whose fundamental behavior is currently unknown. We examine switching behavior by performing time-resolved simulations based on the Landau-Lifshitz-Gilbert (LLG) equation, and find strong and tunable dependence on the polarization angle of the incoming spin current, as well as boundaries between stochastic and deterministic switching. Furthermore, we demonstrate an extension of this concept to enable out-of-plane field-free switching.