Numerical Study on Spin Torque Switching in Thermally Activated Region
  We studied the spin torque switching of the single free layer in the thermally activated region by numerically solving the Landau-Lifshitz-Gilbert equation. We found that the temperature dependence of the switching time of the in-plane magnetized system is nonlinear, which means $b \neq 1$. Here, $b$ is the exponent of the current term in the switching rate formula and has been widely assumed to be unity. This result enables us to evaluate the thermal stability of spintronics devices. 
Tomohiro Taniguchi, Mitsutoshi Shibata, Michael Marthaler, Yasuhiro   Utsumi, and Hiroshi Imamura
cond-mat.mes-hall