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Title: Magnetization reversal in Py/Gd heterostructures

Abstract

Here, using a combination of magnetometry and magnetotransport techniques, we studied temperature and magnetic-field behavior of magnetization in Py/Gd heterostructures. It was shown quantitatively that proximity with Py enhances magnetic order of Gd. Micromagnetic simulations demonstrate that a spin-flop transition observed in a Py/Gd bilayer is due to exchange-spring rotation of magnetization in the Gd layer. Transport measurements show that the magnetoresistance of a [Py(2nm)/Gd(2nm)] 25 multilayer changes sign at the compensation temperature and below 20 K. The positive magnetoresistance above the compensation temperature can be attributed to an in-plane domain wall, which appears because of the structural inhomogeneity of the film over its thickness. By measuring the angular dependence of resistance, we are able to determine the angle between magnetizations in the multilayer and the magnetic field at different temperatures. The measurements reveal that, due to a change in the chemical thickness profile, a noncollinear magnetization configuration is only stable in magnetic fields above 10 kOe.

Authors:
 [1];  [2];  [2];  [2];  [2];  [2]
  1. Argonne National Lab. (ANL), Argonne, IL (United States); Texas A & M Univ., College Station, TX (United States)
  2. Argonne National Lab. (ANL), Argonne, IL (United States)
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1374054
Grant/Contract Number:
AC02-06CH11357
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Physical Review B
Additional Journal Information:
Journal Volume: 96; Journal Issue: 2; Journal ID: ISSN 2469-9950
Publisher:
American Physical Society (APS)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY

Citation Formats

Lapa, Pavel N., Ding, Junjia, Pearson, John E., Novosad, Valentine, Jiang, J. S., and Hoffmann, Axel. Magnetization reversal in Py/Gd heterostructures. United States: N. p., 2017. Web. doi:10.1103/PhysRevB.96.024418.
Lapa, Pavel N., Ding, Junjia, Pearson, John E., Novosad, Valentine, Jiang, J. S., & Hoffmann, Axel. Magnetization reversal in Py/Gd heterostructures. United States. doi:10.1103/PhysRevB.96.024418.
Lapa, Pavel N., Ding, Junjia, Pearson, John E., Novosad, Valentine, Jiang, J. S., and Hoffmann, Axel. 2017. "Magnetization reversal in Py/Gd heterostructures". United States. doi:10.1103/PhysRevB.96.024418.
@article{osti_1374054,
title = {Magnetization reversal in Py/Gd heterostructures},
author = {Lapa, Pavel N. and Ding, Junjia and Pearson, John E. and Novosad, Valentine and Jiang, J. S. and Hoffmann, Axel},
abstractNote = {Here, using a combination of magnetometry and magnetotransport techniques, we studied temperature and magnetic-field behavior of magnetization in Py/Gd heterostructures. It was shown quantitatively that proximity with Py enhances magnetic order of Gd. Micromagnetic simulations demonstrate that a spin-flop transition observed in a Py/Gd bilayer is due to exchange-spring rotation of magnetization in the Gd layer. Transport measurements show that the magnetoresistance of a [Py(2nm)/Gd(2nm)]25 multilayer changes sign at the compensation temperature and below 20 K. The positive magnetoresistance above the compensation temperature can be attributed to an in-plane domain wall, which appears because of the structural inhomogeneity of the film over its thickness. By measuring the angular dependence of resistance, we are able to determine the angle between magnetizations in the multilayer and the magnetic field at different temperatures. The measurements reveal that, due to a change in the chemical thickness profile, a noncollinear magnetization configuration is only stable in magnetic fields above 10 kOe.},
doi = {10.1103/PhysRevB.96.024418},
journal = {Physical Review B},
number = 2,
volume = 96,
place = {United States},
year = 2017,
month = 7
}

Journal Article:
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