The effect of thermal fluctuations on spin-transfer switching has been studied for a broad range of time scales (sub-ns to seconds) in a model system, a uniaxial thin film nanomagnet. The nanomagnet is incorporated into a spin-valve nanopillar, which is subject to spin-polarized current pulses of variable amplitude and duration. Two physical regimes are clearly distinguished: a long pulse duration regime, in which reversal occurs by spin-transfer assisted thermal activation over an energy barrier, and a short time large pulse amplitude regime, in which the switching probability is determined by the spin angular momentum in the current pulse.
@article{arxiv.1009.5240,
title = {Spin-transfer pulse switching: From the dynamic to the thermally activated regime},
author = {D. Bedau and H. Liu and J. Z. Sun and J. A. Katine and E. E. Fullerton and S. Mangin and A. D. Kent},
journal= {arXiv preprint arXiv:1009.5240},
year = {2011}
}