Reduction in switching current density for current-induced magnetization switching without loss of thermal stability: Effect of perpendicular anisotropy

Solving the Landau-Lifshitz-Gilbert-Slonczewski equation numerically, we show that switching current density for the current-induced magnetization switching decreases by introducing the perpendicular anisotropy smaller than the out-of-plane demagnetization energy in the switched layer as predicted by theories. Interestingly, the introduction of the perpendicular anisotropy does not decrease the thermal stability of magnetization, but rather slightly increases. The reduction in switching current density results from the decrease of demagnetization effect whereas the increase of thermal stability results from the decrease of attempt frequency.