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Dislocation loops in overheated free-standing smectic films

A. N. Shalaginov·D. E. Sullivan
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Abstract

Static and dynamic phenomena in overheated free-standing smectic-A films are studied using a generalization of de Gennes' theory for a confined presmectic liquid. A static application is to determine the profile of the film meniscus and the meniscus contact angle, the results being compared with those of a recent study employing de Gennes' original theory. The dynamical generalization of the theory is based on on a time-dependent Ginzburg-Landau approach. This is used to compare two modes for layer-thinning transitions in overheated films, namely "uniform thinning" vs. nucleation of dislocation loops. Properties such as the line tension and velocity of a moving dislocation line are evaluated self-consistently by the theory.

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A. N. Shalaginov, D. E. Sullivan. 2001-10-11. Dislocation loops in overheated free-standing smectic films. https://doi.org/10.1103/physreve.65.031715

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