Reducing the switching current with a Gilbert damping constant in nanomagnets with perpendicular anisotropy

We report on current-induced magnetization switching in a nanomagnet with perpendicular anisotropy, and investigate the effects of the damping constant (alpha) on the switching current (I-sw) by varying the nanosecond-scale pulse current duration (t(p)), the saturation magnetization (M-s), and the magnetocrystalline anisotropy (K-u). The results show that reduction of alpha below a certain threshold (alpha(c)) is ineffective in reducing I-sw for short t(p). When t(p) is short, it is necessary to reduce both a and M-s simultaneously until ac is reached to reduce I-sw. The results presented here offer a promising route for the design of ultrafast information storage and logic devices using current-induced magnetization switching. (C) 2015 AIP Publishing LLC.