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Title: Observation of unidirectional spin Hall magnetoresistance in amorphous PtSn 4 /CoFeB bilayers
Unidirectional spin Hall magnetoresistance (USMR) is a magnetoresistance effect with potential applications to read two-terminal spin–orbit-torque (SOT) devices directly. In this work, we observed a large USMR value (up to 0.7 × 10 −11 per A/cm 2 , 50% larger than reported values from heavy metals) in sputtered amorphous PtSn 4 /CoFeB bilayers. Ta/CoFeB bilayers with interfacial MgO insertion layers are deposited as control samples. The control experiments show that increasing the interfacial resistance can increase the USMR value, which is the case in PtSn 4 /CoFeB bilayers. The observation of a large USMR value in an amorphous spin–orbit-torque material has provided an alternative pathway for USMR application in two-terminal SOT devices.  more » « less
Award ID(s):
2011401
PAR ID:
10411192
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Applied Physics Letters
Volume:
121
Issue:
9
ISSN:
0003-6951
Page Range / eLocation ID:
092401
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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