1307.2496 (D. B. Gopman et al.)

Temperature dependence of the switching field distributions in
all-perpendicular spin-valve nanopillars    [PDF]

D. B. Gopman, D. Bedau, G. Wolf, S. Mangin, E. E. Fullerton, J. A. Katine, A. D. Kent

We present temperature dependent switching measurements of the Co/Ni multilayered free element of 75 nm diameter spin-valve nanopillars. Angular dependent hysteresis measurements as well as switching field measurements taken at low temperature are in agreement with a model of thermal activation over a perpendicular anisotropy barrier. However, the statistics of switching (mean switching field and switching variance) from 20 K up to 400 K are in disagreement with a N\'{e}el-Brown model that assumes a temperature independent barrier height and anisotropy field. We introduce a modified N\'{e}el-Brown model thats fit the experimental data in which we take a $T^{3/2}$ dependence to the barrier height and the anisotropy field due to the temperature dependent magnetization and anisotropy energy.

View original: http://arxiv.org/abs/1307.2496