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This content will become publicly available on September 8, 2024

Title: Sagnac interferometry for high-sensitivity optical measurements of spin-orbit torque

Sagnac interferometry can provide a substantial improvement in signal-to-noise ratio compared to conventional magnetic imaging based on the magneto-optical Kerr effect. We show that this improvement is sufficient to allow quantitative measurements of current-induced magnetic deflections due to spin-orbit torque even in thin-film magnetic samples with perpendicular magnetic anisotropy, for which the Kerr rotation is second order in the magnetic deflection. Sagnac interferometry can also be applied beneficially for samples with in-plane anisotropy, for which the Kerr rotation is first order in the deflection angle. Optical measurements based on Sagnac interferometry can therefore provide a cross-check on electrical techniques for measuring spin-orbit torque. Different electrical techniques commonly give quantitatively inconsistent results so that Sagnac interferometry can help to identify which techniques are affected by unidentified artifacts.

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Award ID(s):
2104268
NSF-PAR ID:
10470817
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
American Association for the Advancement of Science
Date Published:
Journal Name:
Science Advances
Volume:
9
Issue:
36
ISSN:
2375-2548
Page Range / eLocation ID:
eadi9039
Subject(s) / Keyword(s):
["Sagnac interferometry","spin-orbit torque"]
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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