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arXiv · 2004.10109

Hopf solitons in helical and conical backgrounds of chiral magnetic solids

Robert Voinescu·Jung-Shen B. Tai·Ivan I. Smalyukh
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Abstract

Three-dimensional topological solitons attract a great deal of interest in fields ranging from particle physics to cosmology but remain experimentally elusive in solid-state magnets. Here we numerically predict magnetic heliknotons, an embodiment of such nonzero-Hopf-index solitons localized in all spatial dimensions while embedded in a helical or conical background of chiral magnets. We describe conditions under which heliknotons emerge as metastable or ground-state localized nonsingular structures with fascinating knots of magnetization field in widely studied materials. We demonstrate magnetic control of three-dimensional spatial positions of such solitons, as well as show how they interact to form molecule-like clusters and possibly even crystalline phases comprising three-dimensional lattices of such solitons with both orientational and positional order. Finally, we discuss both fundamental importance and potential technological utility of magnetic heliknotons.

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Robert Voinescu, Jung-Shen B. Tai, Ivan I. Smalyukh. 2020-04-21. Hopf solitons in helical and conical backgrounds of chiral magnetic solids. https://doi.org/10.1103/physrevlett.125.057201

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