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Title: Origins of observational errors in field sweep DC measurements for unidirectional magnetoresistance
Understanding the mechanisms of unidirectional magnetoresistance (UMR) has become an important topic for its potential application of a two-terminal spin–orbit torque device. Field sweep DC measurements have been proposed and adopted to measure the value of UMR instead of second harmonic measurements. In this paper, potential measurement errors in conventional DC measurements are investigated. Oersted field and field-like torque usually do not influence the measurement, but a large field-like torque was found to lead to an anisotropic magnetoresistance difference when the sample is not perfectly aligned with the external field. The existence of ordinary magnetoresistance was also found to contribute to a large background. In this paper, an alternative measurement method for UMR was proposed and demonstrated to address those issues related to previous DC measurements. Our work may broaden the understanding of the error sources of UMR measurements and provide a reliable DC measurement method for the characterization of UMR.  more » « less
Award ID(s):
2011401
PAR ID:
10411308
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Journal of Applied Physics
Volume:
132
Issue:
21
ISSN:
0021-8979
Page Range / eLocation ID:
213907
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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