Fast thermally assisted switching at low current density in (Ga,Mn)As magnetic tunnel junctions

摘要

(Ga,Mn)As based magnetic tunnel junctions have potential advantages compared to metal based junctions. In magnetic memory applications, spin-torque switching is the main approach to write information. In addition to the spin-torque effect, the current through the junction also increases the temperature, which can change the coercive fields and switch the magnetization of the (Ga,Mn)As layers in suitable bias fields. Using pulsed currents, we control the temperature increase and switch the junction states with critical current density as low as 3×103 A/cm2 for 100 ns pulses, or with pulses as short as 300 ps at current densities of 5×104 A/cm2.