J. Phys. II France
Volume 4, Numéro 10, October 1994
Page(s) 1633 - 1638
DOI: 10.1051/jp2:1994109
J. Phys. II France 4 (1994) 1633-1638

Nematic distortions in adjustable geometries: repartitioning and instabilities

D.R.M. Williams1 and A. Halperin2

1  Laboratoire de Physique de la Matière Condensée, Collège de France, 75231 Paris Cedex 05, France
2  Laboratoire Léon Brillouin, C.E.N.-Saclay, 91191 Gif-sur-Yvette Cedex, France

(Received 30 November 1993, revised 25 April 1994, accepted 30 August 1994)

Nematic distortion can occur in constraint free systems, where the geometry is adjustable and the nematic is free to repartition itself among various regions. In such cases the nematic distortion gives rise to a term in the free energy which depends on the dimensions of the system. This can produce a mechanical force due to nematic distortions. In turn this leads to a rich phenomenology including a variety of instabilities. Different scenarios are found when the distortions are due to surface alignment and to external fields. These effects are relevant to the understanding of a variety of systems among them nematic gels and nematic systems studied using the force measurement apparatus.

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