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arXiv · 1704.06876

Direct Observation of Attractive Skyrmions and Skyrmion Clusters in the Cubic Helimagnet Cu$_2$OSeO$_3$

J. C. Loudon·A. O. Leonov·A. N. Bogdanov·M. Ciomaga Hatnean·G. Balakrishnan
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Abstract

We report the discovery of attractive magnetic skyrmions and their clusters in non-centrosymmetric ferromagnets. These three-dimensional solitons have been predicted to exist in the cone phase of chiral ferromagnets (J. Phys: Condens. Matter 28 (2016) 35LT01) and are fundamentally different from the more common repulsive axisymmetric skyrmions that occur in the magnetically saturated state. We present real-space images of these skyrmion clusters in thin (~70 nm) single-crystal samples of Cu$_2$OSeO$_3$ taken using transmission electron microscopy and develop a phenomenological theory describing this type of skyrmion.

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J. C. Loudon, A. O. Leonov, A. N. Bogdanov, M. Ciomaga Hatnean, G. Balakrishnan. 2018-03-21. Direct Observation of Attractive Skyrmions and Skyrmion Clusters in the Cubic Helimagnet Cu$_2$OSeO$_3$. https://doi.org/10.1103/physrevb.97.134403

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