Bogomol'nyi bound and screw dislocations in a mesoscopic smectic-A

Eric Akkermans; Sankalpa Ghosh; Amos Schtalheim

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arXiv · cond-mat/0409695

Bogomol'nyi bound and screw dislocations in a mesoscopic smectic-A

Eric Akkermans·Sankalpa Ghosh·Amos Schtalheim

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Abstract

The de Gennes free energy functional of an infinite smectic-A liquid crystal at the dual point is shown to be topological and to depend only on the number of screw dislocations and the anisotropy. This result generalizes the existence of a Bogomol'nyi bound to an anisotropic system. The role of the boundary of a finite mesoscopic smectic is to provide a mechanism for the existence of thermodynamically stable screw dislocations. We obtain a closed expression for the corresponding free energy and a relation between the applied twist and the number of screw dislocations.

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Eric Akkermans, Sankalpa Ghosh, Amos Schtalheim. 2004-09-27. Bogomol'nyi bound and screw dislocations in a mesoscopic smectic-A. https://arxiv.org/abs/cond-mat/0409695

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