Two-pulse magnetic field-free switching scheme for perpendicular SOT-MRAM with a symmetric square free layer

A magnetic field-free switching of a symmetric square free layer with perpendicular magnetization by spin-orbit torque is demonstrated based on micromagnetic modeling and numerical simulations. The field-free switching is accomplished by using a two-pulse switching scheme. An appropriate design of the cell structure yields a deterministic and fast switching, about 0.6 ns, of the magnetized free layer. It is shown that the switching is robust with respect to fluctuations of the current pulse duration and, furthermore, very robust in case of delays or overlaps between the writing current pulses.