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arXiv · 1911.07829

Surface anchoring as a control parameter for stabilizing torons, skyrmions, twisted walls, fingers and their hybrids in chiral nematics

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

Chiral condensed matter systems, such as liquid crystals and magnets, exhibit a host of spatially localized topological structures that emerge from the medium's tendency to twist and its competition with confinement and field coupling effects. We show that the strength of perpendicular surface boundary conditions can be used to control the structure and topology of solitonic and other localized field configurations. By combining numerical modeling and three-dimensional imaging of the director field, we reveal structural stability diagrams and inter-transformation of twisted walls and fingers, torons and skyrmions and their crystalline organizations upon changing boundary conditions. Our findings provide a recipe for controllably realizing skyrmions, torons and hybrid solitonic structures possessing features of both of them, which will aid in fundamental explorations and technological uses of such topological solitons. Moreover, we discuss how other material parameters can be used to determine soliton stability, and how similar principles can be systematically applied to other liquid crystal solitons, and solitons in other material systems.

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Jung-Shen B. Tai, Ivan I. Smalyukh. 2019-11-18. Surface anchoring as a control parameter for stabilizing torons, skyrmions, twisted walls, fingers and their hybrids in chiral nematics. https://doi.org/10.1103/physreve.101.042702

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