Switching dynamics in sub-micrometer spin-valves

Summary form only given. Understanding high-speed magnetization reversal is essential for optimizing MRAM operation. We have investigated reversal in spin-valve devices within the dynamic regime. Nanosecond and sub-nanosecond pulses have been applied both along the longitudinal and the transverse axes of spin-valves. The ensuing responses have been observed via the magnetoresistance on the sub-nanosecond time scale. In the case of transverse pulsing, we have made the first direct observation of reversal due to precessional dynamics which leads to more efficient switching using shorter pulses.