J. Phys. II France
Volume 6, Numéro 6, June 1996
Page(s) 873 - 884
DOI: 10.1051/jp2:1996216
J. Phys. II France 6 (1996) 873-884

Kinetics of the Nematic-Isotropic Interface

V. Popa-Nita and T.J. Sluckin

Faculty of Mathematical Studies, University of Southampton, Southampton SO17 1BJ, UK

(Received 7 April 1995, revised 9 January 1996, accepted 27 February 1996)

We investigate the motion of an interface between a nematic liquid crystal phase and the isotropic phase of the same fluid. In this simplified model we assume the nematic liquid crystal to have one order parameter only and also suppose the system to be isothermal and initially quenched into the metastable régime of the isotropic phase $(T_{\rm NI}>T>T^\ast)$. What results is the time-dependent Ginzburg-Landau equation, with domain wall solutions, corresponding to phase interfaces, which interpolate between static isotropic and nematic minima. These domain walls move with a unique velocity which depends more or less linearly on the degree of undercooling. For real liquid crystals this velocity is of the order of cm s -1. We also examine the relaxation mode solutions of the Ginzburg-Landau equation, and present a complete phase-diagram of these solutions.

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