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  • Separation of Artifacts from Spin‐Torque Ferromagnetic Resonance Measurements of Spin‐Orbit Torque for the Low‐Symmetry Van der Waals Semi‐Metal ZrTe 3
Title: Separation of Artifacts from Spin‐Torque Ferromagnetic Resonance Measurements of Spin‐Orbit Torque for the Low‐Symmetry Van der Waals Semi‐Metal ZrTe 3
Abstract

Spin‐orbit torques generated by exfoliated layers of the low‐symmetry semi‐metal ZrTe3are measured using the spin‐torque ferromagnetic resonance (ST‐FMR) technique. When the ZrTe3has 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 ZrTe3layer 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 Hall geometry as well as the longitudinal geometry. ZrTe3/Permalloy samples generate a conventional in‐plane anti‐damping spin torque efficiency = 0.014 ± 0.004, and an unconventional in‐plane field‐like torque efficiency = 0.003 ± 0.001. The out‐of‐plane anti‐damping torque is negligible. It is suggested that artifacts similarly interfere with the standard ST‐FMR analysis for other van der Waals samples thicker than about 10 nm.

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NSF-PAR ID:
10362531
Author(s) / Creator(s):
 ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Quantum Technologies
Volume:
5
Issue:
2
ISSN:
2511-9044
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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