Solitons attract a great deal of interest in many fields, ranging from optics to fluid mechanics, cosmology, particle physics and condensed matter. However, solitons of these very different types rarely coexist and interact with each other. Here we develop a system that hosts optical solitons coexisting with topological solitonic structures localized in the molecular alignment field of a soft birefringent medium. We experimentally demonstrate and theoretically explain optomechanical interactions between such optical and topological solitons, mediated by the local transfer of momentum between light and matter and the nonlocal orientational elasticity of the liquid-crystal phase used in our system. We show that the delicate balance arising from these different contributions to the optomechanical force enables facile dynamical control and spatial localization of topological solitons. Our findings reveal unusual solitonic tractor beams and emergent light–matter self-patterning phenomena that could aid in creating new breeds of nonlinear photonic materials and devices.
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Experimental research at CU-Boulder was supported by the National Science Foundation through grant DMR-1810513 (A.J.H., A.J.S., M.P. and I.I.S.). G.P. and S.Ž. acknowledge funding from the ARSS (Javna Agencija za Raziskovalno Dejavnost RS) through grant P1-0099 and from the European Union’s Horizon 2020 programme through the Marie Sklodowska-Curie grant agreement no. 834256 and COST European Topology Interdisciplinary Action (EUTOPIA CA17139). A.J.H. thanks the United States’ Office of Science Graduate Student Research (SCGSR) Fellowship for partial project support. A.J.H. also thanks the United States’ National Renewable Energy Laboratory and its Technology Transfer Office for remuneration from the Technology Licensing and Commercialization Fellowship while data were analysed and the manuscript was written. I.I.S. also acknowledges the hospitality of the Chirality Research Center (CResCent) at the University of Hiroshima, Japan, during his sabbatical stay, where he was partly working on this article. We thank P. Ackerman, Y. Yuan, T. Lee and H. Mundoor for discussions.
The authors declare no competing interests.
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Poy, G., Hess, A.J., Seracuse, A.J. et al. Interaction and co-assembly of optical and topological solitons. Nat. Photon. 16, 454–461 (2022). https://doi.org/10.1038/s41566-022-01002-1