Sub-nanosecond switching in a cryogenic spin-torque spin-valve memory element with a dilute permalloy free layer

• DOI: 10.1063/1.5094924
• Publication Date: 2019-05-30T14:42:21Z
• Authors: L. Rehm; V. Sluka; G. E. Rowlands; M.-H. Nguyen; T. A. Ohki; A. D. Kent
• Keywords: Permalloy; Spin valve; Nanosecond; Switching time

We present a study of pulsed current switching characteristics spin-valve nanopillars with in-plane magnetized dilute permalloy and undiluted free layers in the ballistic regime at low temperatures. The layer device switches much faster: characteristic time for (Ni0.83Fe0.17) is 1.18 ns, while that ([Ni0.83Fe0.17]0.6Cu0.4) 0.475 ns. A macrospin model can capture data trends reduced spin-torque asymmetry parameter, spin polarization, increased Gilbert damping relative to devices. Our demonstrates reducing magnetization increases speed greatly energy shows promising route toward even lower power magnetic memory devices compatible superconducting electronics.