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Title: Voltage-controlled interlayer coupling in perpendicularly magnetized magnetic tunnel junctions

Abstract

Magnetic interlayer coupling is one of the central phenomena in spintronics. It has been predicted that the sign of interlayer coupling can be manipulated by electric fields, instead of electric currents, thereby offering a promising low energy magnetization switching mechanism. Here we present the experimental demonstration of voltage-controlled interlayer coupling in a new perpendicular magnetic tunnel junction system with a GdO x tunnel barrier, where a large perpendicular magnetic anisotropy and a sizable tunnelling magnetoresistance have been achieved at room temperature. Owing to the interfacial nature of the magnetism, the ability to move oxygen vacancies within the barrier, and a large proximity-induced magnetization of GdO x, both the magnitude and the sign of the interlayer coupling in these junctions can be directly controlled by voltage. Lastly, these results pave a new path towards achieving energy-efficient magnetization switching by controlling interlayer coupling.

Authors:
 [1]; ORCiD logo [2];  [1];  [3];  [1];  [1];  [1];  [4];  [5];  [5];  [5];  [1];  [1];  [4];  [1];  [3];  [1]
  1. Univ. of Arizona, Tucson, AZ (United States)
  2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
  3. Univ. of Minnesota, Minneapolis, MN (United States)
  4. Bryn Mawr College, Bryn Mawr, PA (United States)
  5. Argonne National Lab. (ANL), Argonne, IL (United States)
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
National Science Foundation (NSF); USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22); U.S. Department of Defense (DOD), Defense Advanced Research Projects Agency (DARPA)
OSTI Identifier:
1357982
Alternate Identifier(s):
OSTI ID: 1372091
Grant/Contract Number:
AC05-00OR22725; AC02-06CH11357
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Nature Communications
Additional Journal Information:
Journal Volume: 8; Journal Issue: 1; Journal ID: ISSN 2041-1723
Publisher:
Nature Publishing Group
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE

Citation Formats

Newhouse-Illige, Ty, Liu, Yaohua, Xu, M., Reifsnyder Hickey, Danielle, Kundu, A., Almasi, H., Bi, Chong, Wang, Xiao, Freeland, J. W., Keavney, D. J., Sun, C. J., Xu, Y. H., Rosales, M., Cheng, X. M., Zhang, Shufeng, Mkhoyan, K. A., and Wang, W. G. Voltage-controlled interlayer coupling in perpendicularly magnetized magnetic tunnel junctions. United States: N. p., 2017. Web. doi:10.1038/ncomms15232.
Newhouse-Illige, Ty, Liu, Yaohua, Xu, M., Reifsnyder Hickey, Danielle, Kundu, A., Almasi, H., Bi, Chong, Wang, Xiao, Freeland, J. W., Keavney, D. J., Sun, C. J., Xu, Y. H., Rosales, M., Cheng, X. M., Zhang, Shufeng, Mkhoyan, K. A., & Wang, W. G. Voltage-controlled interlayer coupling in perpendicularly magnetized magnetic tunnel junctions. United States. doi:10.1038/ncomms15232.
Newhouse-Illige, Ty, Liu, Yaohua, Xu, M., Reifsnyder Hickey, Danielle, Kundu, A., Almasi, H., Bi, Chong, Wang, Xiao, Freeland, J. W., Keavney, D. J., Sun, C. J., Xu, Y. H., Rosales, M., Cheng, X. M., Zhang, Shufeng, Mkhoyan, K. A., and Wang, W. G. Tue . "Voltage-controlled interlayer coupling in perpendicularly magnetized magnetic tunnel junctions". United States. doi:10.1038/ncomms15232. https://www.osti.gov/servlets/purl/1357982.
@article{osti_1357982,
title = {Voltage-controlled interlayer coupling in perpendicularly magnetized magnetic tunnel junctions},
author = {Newhouse-Illige, Ty and Liu, Yaohua and Xu, M. and Reifsnyder Hickey, Danielle and Kundu, A. and Almasi, H. and Bi, Chong and Wang, Xiao and Freeland, J. W. and Keavney, D. J. and Sun, C. J. and Xu, Y. H. and Rosales, M. and Cheng, X. M. and Zhang, Shufeng and Mkhoyan, K. A. and Wang, W. G.},
abstractNote = {Magnetic interlayer coupling is one of the central phenomena in spintronics. It has been predicted that the sign of interlayer coupling can be manipulated by electric fields, instead of electric currents, thereby offering a promising low energy magnetization switching mechanism. Here we present the experimental demonstration of voltage-controlled interlayer coupling in a new perpendicular magnetic tunnel junction system with a GdOx tunnel barrier, where a large perpendicular magnetic anisotropy and a sizable tunnelling magnetoresistance have been achieved at room temperature. Owing to the interfacial nature of the magnetism, the ability to move oxygen vacancies within the barrier, and a large proximity-induced magnetization of GdOx, both the magnitude and the sign of the interlayer coupling in these junctions can be directly controlled by voltage. Lastly, these results pave a new path towards achieving energy-efficient magnetization switching by controlling interlayer coupling.},
doi = {10.1038/ncomms15232},
journal = {Nature Communications},
number = 1,
volume = 8,
place = {United States},
year = {Tue May 16 00:00:00 EDT 2017},
month = {Tue May 16 00:00:00 EDT 2017}
}

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  • Magnetic interlayer coupling is one of the central phenomena in spintronics. It has been predicted that the sign of interlayer coupling can be manipulated by electric fields, instead of electric currents, thereby offering a promising low energy magnetization switching mechanism. Here we present the experimental demonstration of voltage-controlled interlayer coupling in a new perpendicular magnetic tunnel junction system with a GdOx tunnel barrier, where a large perpendicular magnetic anisotropy and a sizable tunnelling magnetoresistance have been achieved at room temperature. Owing to the interfacial nature of the magnetism, the ability to move oxygen vacancies within the barrier, and a largemore » proximity-induced magnetization of GdOx, both the magnitude and the sign of the interlayer coupling in these junctions can be directly controlled by voltage. These results pave a new path towards achieving energy-efficient magnetization switching by controlling interlayer coupling.« less
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  • Interlayer exchange coupling of two ferromagnetic electrodes separated by a thin MgO tunnel barrier is investigated using magneto-optical Kerr effect. We find that the coupling field can be reduced by more than 40% as the thickness of a top Ta capping layer increases from 0.5 to 1.2 nm. In contrast, a similar film stack with an additional 3 nm Ru capping layer displays no such dependence on Ta thickness. Transmission electron microscopy study shows that the oxidation of the exposed Ta capping layer induces changes in the crystalline structures of the underlying films, giving rise to the observed reduction ofmore » the interlayer coupling field.« less