Universal current-velocity relation of skyrmion motion in chiral magnets

Junichi Iwasaki, Masahito Mochizuki, Naoto Nagaosa

Research output: Contribution to journalArticle

287 Citations (Scopus)

Abstract

Current-driven motion of the magnetic domain wall in ferromagnets is attracting intense attention because of potential applications such as racetrack memory. There, the critical current density to drive the motion is ∼10 9 -10 12 A m -2. The skyrmions recently discovered in chiral magnets have much smaller critical current density of ∼10 5 -10 6 A m -2, but the microscopic mechanism is not yet explored. Here we present a numerical simulation of Landau-Lifshitz-Gilbert equation, which reveals a remarkably robust and universal current-velocity relation of the skyrmion motion driven by the spin-transfer-torque unaffected by either impurities or nonadiabatic effect in sharp contrast to the case of domain wall or spin helix. Simulation results are analysed using a theory based on Thiele's equation, and it is concluded that this behaviour is due to the Magnus force and flexible shape-deformation of individual skyrmions and skyrmion crystal, which enable them to avoid pinning centres.

Original languageEnglish
Article number1463
JournalNature Communications
Volume4
DOIs
Publication statusPublished - 2013
Externally publishedYes

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Magnets
Domain walls
magnets
Magnetic domains
domain wall
critical current
current density
Torque
Impurities
magnetic domains
Data storage equipment
helices
Crystals
torque
Computer simulation
simulation
impurities
crystals

ASJC Scopus subject areas

  • Biochemistry, Genetics and Molecular Biology(all)
  • Chemistry(all)
  • Physics and Astronomy(all)

Cite this

Universal current-velocity relation of skyrmion motion in chiral magnets. / Iwasaki, Junichi; Mochizuki, Masahito; Nagaosa, Naoto.

In: Nature Communications, Vol. 4, 1463, 2013.

Research output: Contribution to journalArticle

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