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arXiv · 1709.08047

Skyrmion formation in a bulk chiral magnet at zero magnetic field and above room temperature

K. Karube·J. S. White·D. Morikawa·M. Bartkowiak·A. Kikkawa·Y. Tokunaga·T. Arima·H. M. Rønnow·Y. Tokura·Y. Taguchi
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Abstract

We report that in a $\beta$-Mn-type chiral magnet Co$_9$Zn$_9$Mn$_2$, skyrmions are realized as a metastable state over a wide temperature range, including room temperature, via field-cooling through the thermodynamic equilibrium skyrmion phase that exists below a transition temperature $T_\mathrm{c}$ $\sim$ 400 K. The once-created metastable skyrmions survive at zero magnetic field both at and above room temperature. Such robust skyrmions in a wide temperature and magnetic field region demonstrate the key role of topology, and provide a significant step toward technological applications of skyrmions in bulk chiral magnets.

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K. Karube, J. S. White, D. Morikawa, M. Bartkowiak, A. Kikkawa, Y. Tokunaga, T. Arima, H. M. Rønnow, Y. Tokura, Y. Taguchi. 2017-09-23. Skyrmion formation in a bulk chiral magnet at zero magnetic field and above room temperature. https://doi.org/10.1103/physrevmaterials.1.074405

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