skip to main content

Title: Transverse and Longitudinal Spin-Torque Ferromagnetic Resonance for Improved Measurement of Spin-Orbit Torque
Authors:
; ; ;
Award ID(s):
1708499
Publication Date:
NSF-PAR ID:
10189558
Journal Name:
Physical Review Applied
Volume:
14
Issue:
2
ISSN:
2331-7019
Sponsoring Org:
National Science Foundation
More Like this
  1. We measure spin-orbit torque generated by exfoliated layers of the low-symmetry semi-metal ZrTe3 using the spin-torque ferromagnetic resonance (ST-FMR) technique. When the ZrTe3 has a thickness greater than about 10 nm, artifacts due to spin pumping and/or resonant heating can cause the standard ST-FMR analysis to overestimate the true magnitude of the torque efficiency by as much as a factor of 30, and to indicate incorrectly that the spin-orbit torque depends strongly on the ZrTe3 layer thickness. Artifact-free measurements can still be achieved over a substantial thickness range by the method developed recently to detect ST-FMR signals in the Hallmore »geometry as well as the longitudinal geometry. ZrTe3/Permalloy samples generate a conventional in-plane anti-damping spin torque efficiency ξDL|| = 0.014 ± 0.004, and an unconventional in-plane field-like torque efficiency |ξFL||| = 0.003 ± 0.001. The out-of-plane anti-damping torque is negligible. We suggest that artifacts similarly interfere with the standard ST-FMR analysis for other van der Waals samples thicker than about 10 nm.« less