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Title: Thickness dependence of spin Hall magnetoresistance in FeMn/Pt bilayers

Abstract

We investigated spin Hall magnetoresistance in FeMn/Pt bilayers, which was found to be one order of magnitude larger than that of heavy metal and insulating ferromagnet or antiferromagnet bilayer systems, and comparable to that of NiFe/Pt bilayers. The spin Hall magnetoresistance shows a non-monotonic dependence on the thicknesses of both FeMn and Pt. The former can be accounted for by the thickness dependence of net magnetization in FeMn thin films, whereas the latter is mainly due to spin accumulation and diffusion in Pt. Through analysis of the Pt thickness dependence, the spin Hall angle, spin diffusion length of Pt and the real part of spin mixing conductance were determined to be 0.2, 1.1 nm, and 5.5 × 10{sup 14} Ω{sup −1}m{sup −2}, respectively. The results corroborate the spin orbit torque effect observed in this system recently.

Authors:
 [1];  [2]; ;  [1];  [3]
  1. Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore 117583 (Singapore)
  2. (Agency for Science, Technology and Research), 2 Fusionopolis Way, 08-03 Innovis, Singapore 138634 (Singapore)
  3. Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology and Research), 2 Fusionopolis Way, 08-03 Innovis, Singapore 138634 (Singapore)
Publication Date:
OSTI Identifier:
22611544
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Advances; Journal Volume: 6; Journal Issue: 6; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; BINARY ALLOY SYSTEMS; BUILDUP; COMPARATIVE EVALUATIONS; DIFFUSION; DIFFUSION LENGTH; HEAVY METALS; IRON COMPOUNDS; LAYERS; MAGNETIZATION; MAGNETORESISTANCE; MANGANESE COMPOUNDS; PLATINUM; SPIN; THICKNESS; THIN FILMS; TORQUE

Citation Formats

Yang, Yumeng, Institute of Materials Research and Engineering, A*STAR, Xu, Yanjun, Wu, Yihong, E-mail: elewuyh@nus.edu.sg, and Yao, Kui. Thickness dependence of spin Hall magnetoresistance in FeMn/Pt bilayers. United States: N. p., 2016. Web. doi:10.1063/1.4953396.
Yang, Yumeng, Institute of Materials Research and Engineering, A*STAR, Xu, Yanjun, Wu, Yihong, E-mail: elewuyh@nus.edu.sg, & Yao, Kui. Thickness dependence of spin Hall magnetoresistance in FeMn/Pt bilayers. United States. doi:10.1063/1.4953396.
Yang, Yumeng, Institute of Materials Research and Engineering, A*STAR, Xu, Yanjun, Wu, Yihong, E-mail: elewuyh@nus.edu.sg, and Yao, Kui. 2016. "Thickness dependence of spin Hall magnetoresistance in FeMn/Pt bilayers". United States. doi:10.1063/1.4953396.
@article{osti_22611544,
title = {Thickness dependence of spin Hall magnetoresistance in FeMn/Pt bilayers},
author = {Yang, Yumeng and Institute of Materials Research and Engineering, A*STAR and Xu, Yanjun and Wu, Yihong, E-mail: elewuyh@nus.edu.sg and Yao, Kui},
abstractNote = {We investigated spin Hall magnetoresistance in FeMn/Pt bilayers, which was found to be one order of magnitude larger than that of heavy metal and insulating ferromagnet or antiferromagnet bilayer systems, and comparable to that of NiFe/Pt bilayers. The spin Hall magnetoresistance shows a non-monotonic dependence on the thicknesses of both FeMn and Pt. The former can be accounted for by the thickness dependence of net magnetization in FeMn thin films, whereas the latter is mainly due to spin accumulation and diffusion in Pt. Through analysis of the Pt thickness dependence, the spin Hall angle, spin diffusion length of Pt and the real part of spin mixing conductance were determined to be 0.2, 1.1 nm, and 5.5 × 10{sup 14} Ω{sup −1}m{sup −2}, respectively. The results corroborate the spin orbit torque effect observed in this system recently.},
doi = {10.1063/1.4953396},
journal = {AIP Advances},
number = 6,
volume = 6,
place = {United States},
year = 2016,
month = 6
}
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