Thermally activated sweep-rate dependence of magnetic switching field in nanostructured current-perpendicular spin-valves

We report on the thermal-activation nature of magnetic switching in magnetic nanostructures, using the junction magnetoresistance of a current-perpendicular magnetic spin-valve device as a probe. A spin-valve junction structure was fabricated using electron-beam lithography. A sweep-rate-dependent magnetic switching field was obtained in the quasi-static limit. Results confirm the predictions of a single-domain thermal activation model. The scaling relation between the magnetic field sweep rate, the magnetic switching field, and the sample size is verified for sample dimensions of 0.1 × 0.2 μm2. © 2002 Elsevier Science B.V. All rights reserved.