Second-harmonic signature of chiral spin structures in W/Pt/Co heterostructures with tunable magnetic anisotropy

Authors

Yang Wang, University of Delaware
Ying-Ting Chan, Rutgers University - New Brunswick/Piscataway
Xiao Wang, Bryn Mawr College
Tao Wang, University of Delaware
Xuemei Cheng, Bryn Mawr CollegeFollow
Weida Wu, Rutgers University - New Brunswick/Piscataway
John Q. Xiao, University of Delaware

Document Type

Article

Version

Author's Final Manuscript

Publication Title

Journal of Physics D: Applied Physics

Volume

56

Publication Date

2023

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.

Citation

Yang Wang et al. 2023. "Second-harmonic signature of chiral spin structures in W/Pt/Co heterostructures with tunable magnetic anisotropy." J. Phys. D: Appl. Phys. 56: 205002.

DOI

http://doi.org/10.1088/1361-6463/acc40f