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Title: Structural and magnetic depth profiles of magneto-ionic heterostructures beyond the interface limit

Abstract

Electric field control of magnetism provides a promising route towards ultralow power information storage and sensor technologies. The effects of magneto-ionic motion have been prominently featured in the modification of interface characteristics. Here, we demonstrate magnetoelectric coupling moderated by voltage-driven oxygen migration beyond the interface in relatively thick AlO x/GdO x/Co(15 nm) films. Oxygen migration and Co magnetization are quantitatively mapped with polarized neutron reflectometry under electro-thermal conditioning. The depth-resolved profiles uniquely identify interfacial and bulk behaviours and a semi-reversible control of the magnetization. Magnetometry measurements suggest changes in the microstructure which disrupt long-range ferromagnetic ordering, resulting in an additional magnetically soft phase. X-ray spectroscopy confirms changes in the Co oxidation state, but not in the Gd, suggesting that the GdO x transmits oxygen but does not source or sink it. These results together provide crucial insight into controlling magnetism via magneto-ionic motion, both at interfaces and throughout the bulk of the films.

Authors:
ORCiD logo [1];  [1];  [2]; ORCiD logo [3];  [1];  [1];  [1]
  1. National Institute of Standards and Technology, Gaithersburg, MD (United States)
  2. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
  3. Univ. of California, Davis, CA (United States)
Publication Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1378347
DOE Contract Number:
AC02-05CH11231
Resource Type:
Journal Article
Resource Relation:
Journal Name: Nature Communications; Journal Volume: 7
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; Electronic properties and materials; Magnetic properties and materials; Nanoscale materials; Surfaces, interfaces and thin films

Citation Formats

Gilbert, Dustin A., Grutter, Alexander J., Arenholz, Elke, Liu, Kai, Kirby, B. J., Borchers, Julie A., and Maranville, Brian B. Structural and magnetic depth profiles of magneto-ionic heterostructures beyond the interface limit. United States: N. p., 2016. Web. doi:10.1038/ncomms12264.
Gilbert, Dustin A., Grutter, Alexander J., Arenholz, Elke, Liu, Kai, Kirby, B. J., Borchers, Julie A., & Maranville, Brian B. Structural and magnetic depth profiles of magneto-ionic heterostructures beyond the interface limit. United States. doi:10.1038/ncomms12264.
Gilbert, Dustin A., Grutter, Alexander J., Arenholz, Elke, Liu, Kai, Kirby, B. J., Borchers, Julie A., and Maranville, Brian B. 2016. "Structural and magnetic depth profiles of magneto-ionic heterostructures beyond the interface limit". United States. doi:10.1038/ncomms12264. https://www.osti.gov/servlets/purl/1378347.
@article{osti_1378347,
title = {Structural and magnetic depth profiles of magneto-ionic heterostructures beyond the interface limit},
author = {Gilbert, Dustin A. and Grutter, Alexander J. and Arenholz, Elke and Liu, Kai and Kirby, B. J. and Borchers, Julie A. and Maranville, Brian B.},
abstractNote = {Electric field control of magnetism provides a promising route towards ultralow power information storage and sensor technologies. The effects of magneto-ionic motion have been prominently featured in the modification of interface characteristics. Here, we demonstrate magnetoelectric coupling moderated by voltage-driven oxygen migration beyond the interface in relatively thick AlOx/GdOx/Co(15 nm) films. Oxygen migration and Co magnetization are quantitatively mapped with polarized neutron reflectometry under electro-thermal conditioning. The depth-resolved profiles uniquely identify interfacial and bulk behaviours and a semi-reversible control of the magnetization. Magnetometry measurements suggest changes in the microstructure which disrupt long-range ferromagnetic ordering, resulting in an additional magnetically soft phase. X-ray spectroscopy confirms changes in the Co oxidation state, but not in the Gd, suggesting that the GdOx transmits oxygen but does not source or sink it. These results together provide crucial insight into controlling magnetism via magneto-ionic motion, both at interfaces and throughout the bulk of the films.},
doi = {10.1038/ncomms12264},
journal = {Nature Communications},
number = ,
volume = 7,
place = {United States},
year = 2016,
month = 7
}
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