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Title: Spin-orbit torque-driven skyrmion dynamics revealed by time-resolved X-ray microscopy

Abstract

Magnetic skyrmions are topologically protected spin textures with attractive properties suitable for high-density and low-power spintronic device applications. Much effort has been dedicated to understanding the dynamical behaviours of the magnetic skyrmions. However, experimental observation of the ultrafast dynamics of this chiral magnetic texture in real space, which is the hallmark of its quasiparticle nature, has so far remained elusive. Here, we report nanosecond-dynamics of a 100nm-diameter magnetic skyrmion during a current pulse application, using a time-resolved pump-probe soft X-ray imaging technique. We demonstrate that distinct dynamic excitation states of magnetic skyrmions, triggered by current-induced spin-orbit torques, can be reliably tuned by changing the magnitude of spin-orbit torques. Our findings show that the dynamics of magnetic skyrmions can be controlled by the spin-orbit torque on the nanosecond time scale, which points to exciting opportunities for ultrafast and novel skyrmionic appl ications in the future.

Authors:
ORCiD logo [1];  [2];  [3];  [4];  [5]; ORCiD logo [3];  [1]; ORCiD logo [6];  [7];  [1]; ORCiD logo [1];  [1];  [1]
  1. Korea Inst. of Science and Technology, Seoul (Korea) Center for Spintronics
  2. Korea Inst. of Science and Technology, Seoul (Korea) Center for Spintronics; Sookmyung Women's Univ., Seoul (Korea). Dept of Physics
  3. Ulsan National Inst. of Science and Technology, Ulsan (Korea). School of Materials Science and Engineering
  4. Daegu Gyeongbuk Inst. of Science and Technology (DGIST), Daegu (Korea). Dept. of Emerging Materials Science
  5. Daegu Gyeongbuk Inst. of Science and Technology (DGIST), Daegu (Korea). Research Center for Emerging Materials; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Center for X-ray Optics
  6. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Materials Sciences Division
  7. Daegu Gyeongbuk Inst. of Science and Technology (DGIST), Daegu (Korea). Dept. of Emerging Materials Science, Research Center for Emerging Materials
Publication Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1379861
Grant/Contract Number:
AC02-05CH11231
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Nature Communications
Additional Journal Information:
Journal Volume: 8; Journal ID: ISSN 2041-1723
Publisher:
Nature Publishing Group
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 36 MATERIALS SCIENCE; magnetic properties and materials; spintronics

Citation Formats

Woo, Seonghoon, Song, Kyung Mee, Han, Hee-Sung, Jung, Min-Seung, Im, Mi-Young, Lee, Ki-Suk, Song, Kun Soo, Fischer, Peter, Hong, Jung-Il, Choi, Jun Woo, Min, Byoung-Chul, Koo, Hyun Cheol, and Chang, Joonyeon. Spin-orbit torque-driven skyrmion dynamics revealed by time-resolved X-ray microscopy. United States: N. p., 2017. Web. doi:10.1038/ncomms15573.
Woo, Seonghoon, Song, Kyung Mee, Han, Hee-Sung, Jung, Min-Seung, Im, Mi-Young, Lee, Ki-Suk, Song, Kun Soo, Fischer, Peter, Hong, Jung-Il, Choi, Jun Woo, Min, Byoung-Chul, Koo, Hyun Cheol, & Chang, Joonyeon. Spin-orbit torque-driven skyrmion dynamics revealed by time-resolved X-ray microscopy. United States. doi:10.1038/ncomms15573.
Woo, Seonghoon, Song, Kyung Mee, Han, Hee-Sung, Jung, Min-Seung, Im, Mi-Young, Lee, Ki-Suk, Song, Kun Soo, Fischer, Peter, Hong, Jung-Il, Choi, Jun Woo, Min, Byoung-Chul, Koo, Hyun Cheol, and Chang, Joonyeon. Wed . "Spin-orbit torque-driven skyrmion dynamics revealed by time-resolved X-ray microscopy". United States. doi:10.1038/ncomms15573. https://www.osti.gov/servlets/purl/1379861.
@article{osti_1379861,
title = {Spin-orbit torque-driven skyrmion dynamics revealed by time-resolved X-ray microscopy},
author = {Woo, Seonghoon and Song, Kyung Mee and Han, Hee-Sung and Jung, Min-Seung and Im, Mi-Young and Lee, Ki-Suk and Song, Kun Soo and Fischer, Peter and Hong, Jung-Il and Choi, Jun Woo and Min, Byoung-Chul and Koo, Hyun Cheol and Chang, Joonyeon},
abstractNote = {Magnetic skyrmions are topologically protected spin textures with attractive properties suitable for high-density and low-power spintronic device applications. Much effort has been dedicated to understanding the dynamical behaviours of the magnetic skyrmions. However, experimental observation of the ultrafast dynamics of this chiral magnetic texture in real space, which is the hallmark of its quasiparticle nature, has so far remained elusive. Here, we report nanosecond-dynamics of a 100nm-diameter magnetic skyrmion during a current pulse application, using a time-resolved pump-probe soft X-ray imaging technique. We demonstrate that distinct dynamic excitation states of magnetic skyrmions, triggered by current-induced spin-orbit torques, can be reliably tuned by changing the magnitude of spin-orbit torques. Our findings show that the dynamics of magnetic skyrmions can be controlled by the spin-orbit torque on the nanosecond time scale, which points to exciting opportunities for ultrafast and novel skyrmionic appl ications in the future.},
doi = {10.1038/ncomms15573},
journal = {Nature Communications},
number = ,
volume = 8,
place = {United States},
year = {Wed May 24 00:00:00 EDT 2017},
month = {Wed May 24 00:00:00 EDT 2017}
}

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