Thermally assisted magnetic switching of a single perpendicularly magnetized layer induced by an in-plane current

We report that by heating samples the critical current density for magnetization reversal (Jc) in a single perpendicularly magnetized layer can be decreased from 2.6 × 107 A/cm2 to about 1 × 106 A/cm2 for a temperature increase of 143 K. The nonlinear dependence of Jc on the perpendicular anisotropy field indicates that the coherent magnetic switching model cannot fully explain the current-induced perpendicular switching. By considering the current-induced domain nucleation and expansion during switching, we conclude that Jc also depends on current-induced domain behavior. Moreover, by reversing the heat flow direction, we demonstrate that the thermal related spin transfer torques have little influence on the thermally assisted magnetic switching.