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Title: Vortex dynamics and frequency splitting in vertically coupled nanomagnets

Abstract

Here, we explored the dynamic response of a vortex core in a circular nanomagnet by manipulating its dipole-dipole interaction with another vortex core confined locally on top of the nanomagnet. A clear frequency splitting is observed corresponding to the gyrofrequencies of the two vortex cores. The peak positions of the two resonance frequencies can be engineered by controlling the magnitude and direction of the external magnetic field. Both experimental and micromagnetic simulations show that the frequency spectra for the combined system is significantly dependent on the chirality of the circular nanomagnet and is asymmetric with respect to the external bias field. We attribute this result to the strong dynamic dipole-dipole interaction between the two vortex cores, which varies with the distance between them. The possibility of having multiple states in a single nanomagnet with vertical coupling could be of interest for magnetoresistive memories.

Authors:
 [1];  [2];  [1];  [3];  [3];  [1];  [1];  [1];  [4];  [4]; ORCiD logo [5];  [4]
  1. Far Eastern Federal Univ., Vladivostok (Russia)
  2. Argonne National Lab. (ANL), Argonne, IL (United States); Western Digital, San Jose, CA (United States)
  3. Far Eastern Federal Univ., Vladivostok (Russia); National Research South Ural State Univ., Chelyabinsk (Russia)
  4. Argonne National Lab. (ANL), Argonne, IL (United States)
  5. National Univ. of Science and Technology ("MISiS"), Moscow (Russia); National Research South Ural State Univ., Chelyabinsk (Russia)
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
Ministry of Education and Science of the Russian Federation; USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22); Materials Sciences and Engineering Division; Russian Foundation for Basic Research
OSTI Identifier:
1352925
Grant/Contract Number:
AC02-06CH11357
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Scientific Reports
Additional Journal Information:
Journal Volume: 7; Journal Issue: 1; Journal ID: ISSN 2045-2322
Publisher:
Nature Publishing Group
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; materials scienc; nanoscale materials

Citation Formats

Stebliy, M. E., Jain, S., Kolesnikov, A. G., Ognev, A. V., Samardak, A. S., Davydenko, A. V., Sukovatitcina, E. V., Chebotkevich, L. A., Ding, J., Pearson, J., Khovaylo, V., and Novosad, V.. Vortex dynamics and frequency splitting in vertically coupled nanomagnets. United States: N. p., 2017. Web. doi:10.1038/s41598-017-01222-4.
Stebliy, M. E., Jain, S., Kolesnikov, A. G., Ognev, A. V., Samardak, A. S., Davydenko, A. V., Sukovatitcina, E. V., Chebotkevich, L. A., Ding, J., Pearson, J., Khovaylo, V., & Novosad, V.. Vortex dynamics and frequency splitting in vertically coupled nanomagnets. United States. doi:10.1038/s41598-017-01222-4.
Stebliy, M. E., Jain, S., Kolesnikov, A. G., Ognev, A. V., Samardak, A. S., Davydenko, A. V., Sukovatitcina, E. V., Chebotkevich, L. A., Ding, J., Pearson, J., Khovaylo, V., and Novosad, V.. Tue . "Vortex dynamics and frequency splitting in vertically coupled nanomagnets". United States. doi:10.1038/s41598-017-01222-4. https://www.osti.gov/servlets/purl/1352925.
@article{osti_1352925,
title = {Vortex dynamics and frequency splitting in vertically coupled nanomagnets},
author = {Stebliy, M. E. and Jain, S. and Kolesnikov, A. G. and Ognev, A. V. and Samardak, A. S. and Davydenko, A. V. and Sukovatitcina, E. V. and Chebotkevich, L. A. and Ding, J. and Pearson, J. and Khovaylo, V. and Novosad, V.},
abstractNote = {Here, we explored the dynamic response of a vortex core in a circular nanomagnet by manipulating its dipole-dipole interaction with another vortex core confined locally on top of the nanomagnet. A clear frequency splitting is observed corresponding to the gyrofrequencies of the two vortex cores. The peak positions of the two resonance frequencies can be engineered by controlling the magnitude and direction of the external magnetic field. Both experimental and micromagnetic simulations show that the frequency spectra for the combined system is significantly dependent on the chirality of the circular nanomagnet and is asymmetric with respect to the external bias field. We attribute this result to the strong dynamic dipole-dipole interaction between the two vortex cores, which varies with the distance between them. The possibility of having multiple states in a single nanomagnet with vertical coupling could be of interest for magnetoresistive memories.},
doi = {10.1038/s41598-017-01222-4},
journal = {Scientific Reports},
number = 1,
volume = 7,
place = {United States},
year = {Tue Apr 25 00:00:00 EDT 2017},
month = {Tue Apr 25 00:00:00 EDT 2017}
}

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