Switching in Spin-Valve Devices in Response to Subnanosecond Longitudinal Field Pulses
Shehzaad F. Kaka, Stephen E. Russek
We have fabricated spin-valve devices in a high-speed test structure that allows subnanosecond pulsed field excitation and high-bandwidth observation of the magnetoresistance response. The switching response varies for low-amplitude field pulses and approaches a consistent fast switch of less than 1 ns for field pulses of higher amplitude. For several pulse widths and amplitudes, the device switches into metastable states. The threshold amplitude fo the write-pulse was measured as a function of pulse duration for pulses as small as 250 ps in duration.