Sluggish steady flow of skyrmion lattice in a confined geometry

ORAL

Abstract

An aggregate of magnetic skyrmions1,2, topologically protected particlelike objects, is an emerging exotic fluid that flows under electric current3,4. From a hydrodynamics point of view, the skyrmion fluid is peculiar in that its steady flow does not necessarily require a closed-loop skyrmion circuit. However, it remains largely unclear how this peculiarity is involved in the skyrmion steady-flow dynamics. Here, we show that the skyrmion steady flow dramatically slowdowns when the influence of system edges is not negligible. In the micrometre-sized MnSi, the steady-flow velocity is anomalously slow, as evidenced by the observation of resistance narrow-band noise with 10–104 Hz, and its temperature evolution suggests that the steady flow entails thermally activated processes, which are due most likely to the skyrmion creation and annihilation at the edges. Moreover, numerical simulations reveal that the edges limit the skyrmion motion. Thus, our findings capture a vital role of the edges on the skyrmion steady flow, especially in a microstructure.

1. S. Mühlbauer, et al. Science 323, 915-919 (2009).
2. X. Z. Yu, et al. Nature 465, 901-904 (2010).
3. F. Jonietz, et al. Science 330, 1648-1651 (2010).
4. T. Schulz, et al. Nat. Phys. 8, 301-304 (2012).

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Presenters

  • Takuro Sato

    • RIKEN Center for Emergent Matter Science (CEMS)

Authors

  • Takuro Sato

    • RIKEN Center for Emergent Matter Science (CEMS)

  • Wataru Koshibae

    • RIKEN Center for Emergent Matter Science (CEMS)
    • RIKEN CEMS

  • Akiko Kikkawa

    • RIKEN Center for Emergent Matter Science (CEMS)
    • RIKEN Center for Emergent Matter Science
    • Center for Emergent Matter Science (CEMS), RIKEN

  • Tomoyuki Yokouchi

    • RIKEN Center for Emergent Matter Science (CEMS)

  • Hiroshi Oike

    • The University of Tokyo

  • Yasujiro Taguchi

    • RIKEN Center for Emergent Matter Science (CEMS)
    • RIKEN Center for Emergent Matter Science
    • RIKEN Center for Emergent Matter Science (CEMS), Wako, Japan
    • Center for Emergent Matter Science (CEMS), RIKEN
    • RIKEN Center for Emergent Matter Science (CEMS), Wako, Japan.

  • Naoto Nagaosa

    • University of Tokyo, Riken CEMS
    • Department of Applied Physics, University of Tokyo
    • RIKEN Center for Emergent Matter Science (CEMS)
    • RIKEN CEMS
    • Center for Emergent Matter Science, RIKEN
    • RIKEN
    • Department of applied physics, The University of Tokyo
    • Department of Applied Physics, Universtiy of Tokyo
    • University of Tokyo

  • Yoshinori Tokura

    • RIKEN Center for Emergent Matter Science (CEMS)
    • RIKEN Center for Emergent Matter Science
    • RIKEN CEMS
    • RIKEN Center for Emergent Matter Science (CEMS), Wako, Japan
    • Center for Emergent Matter Science (CEMS), RIKEN
    • Department of Applied Physics and Quantum-Phase Electronics Center, University of Tokyo
    • University of Tokyo
    • University of Tokyo and RIKEN CEMS
    • CEMS, RIKEN
    • Center for Emergent Matter Science, RIKEN
    • Department of Applied Physics, University of Tokyo
    • University of Tokyo and RIKEN-CEMS

  • Fumitaka Kagawa

    • RIKEN Center for Emergent Matter Science (CEMS)
    • Center for Emergent Matter Science (CEMS), RIKEN