Sub-nanosecond switching in a cryogenic spin-torque spin-valve memory element with a dilute permalloy free layer
Abstract
We present a study of pulsed current switching characteristics of spin-valve nanopillars with in-plane magnetized dilute permalloy and undiluted permalloy free layers in the ballistic regime at low temperatures. The dilute permalloy free layer device switches much faster: the characteristic switching time for a permalloy (Ni0.83Fe0.17) free layer device is 1.18 ns, while that for a dilute permalloy ([Ni0.83Fe0.17]0.6Cu0.4) free layer device is 0.475 ns. A ballistic macrospin model can capture the data trends with a reduced spin-torque asymmetry parameter, reduced spin polarization, and increased Gilbert damping for the dilute permalloy free layer relative to the permalloy devices. Our study demonstrates that reducing the magnetization of the free layer increases the switching speed while greatly reducing the switching energy and shows a promising route toward even lower power magnetic memory devices compatible with superconducting electronics.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- May 27, 2019
- Source ID
- 10.1063/1.5094924
Entities
People
- Andrew D. Kent
- Graham E. Rowlands
- L. Rehm
- Minh-Hai Nguyen
- Thomas Ohki
- V. Sluka
Organizations
- Intelligence Advanced Research Projects Activity
- New York University
- RTX