Thermal effects on the critical current of spin torque switching in spin valve nanopillars
Michael L. Schneider, Matthew R. Pufall, William H. Rippard, Stephen E. Russek, Jordan A. Katine
In spin valve nanopillars, temperature affects the spin torque reversal of the free magnetic layer. The authors compare values of zero temperature critical switching current Ic0 extrapolated from room temperature pulsed current switching measurements to those of quasistatic current sweeps at 5 K. The values extrapolated from the room temperature pulsed switching probability measurements always less than or equal to those of the low temperature quasistatic measurements. Further the room temperature device-to-device variations of the critical switching current are drastically reduced at low temperature, where Ic0 agrees with the theory. Finally, the authors find that Ic0 scales with the free layer volume, as expected.