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Title: Second-harmonic signature of chiral spin structures in W/Pt/Co heterostructures with tunable magnetic anisotropy
Abstract Second-harmonic Hall voltage (SHV) measurement method has been widely used to characterize the strengths of spin–orbit torques (SOTs) in heavy metal/ferromagnet thin films saturated in the single-domain regime. Here, we show that the magnetic anisotropy of a W/Pt/Co trilayer can be robustly tuned from in-plane to out-of-plane by varying W, Pt, or Co thicknesses. Moreover, in samples with easy-cone anisotropy, SHV measurements exhibit anomalous ‘humps’ in the multidomain regime accessed by applying a nearly out-of-plane external magnetic field. These hump features can only be explained as a result of the formation of Néel-type domain walls, efficiently driven by nevertheless small SOTs in this double heavy metal heterostructure with canceling spin Hall angles.  more » « less
Award ID(s):
1904076
NSF-PAR ID:
10426883
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
Journal of Physics D: Applied Physics
Volume:
56
Issue:
20
ISSN:
0022-3727
Page Range / eLocation ID:
205002
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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