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arXiv · 2105.04822

Tailored Nematic and Magnetization Profiles on 2D Polygons

Yucen Han·Joseph Harris·Joshua Walton·Apala Majumdar
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Abstract

We study dilute suspensions of magnetic nanoparticles in a nematic host, on two-dimensional (2D) polygons. These systems are described by a nematic order parameter and a spontaneous magnetization, in the absence of any external fields. We study the stable states in terms of stable critical points of an appropriately defined free energy, with a nemato-magnetic coupling energy. We numerically study the interplay between the shape of the regular polygon, the size of the polygon and the strength of the nemato-magnetic coupling for the multistability of this prototype system. Our notable results include (i) the co-existence of stable states with domain walls and stable interior and boundary defects, (ii) the suppression of multistability for positive nemato-magnetic coupling, and (iii) the enhancement of multistability for negative nemato-magnetic coupling.

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Yucen Han, Joseph Harris, Joshua Walton, Apala Majumdar. 2021-05-11. Tailored Nematic and Magnetization Profiles on 2D Polygons. https://doi.org/10.1103/physreve.103.052702

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