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Liquid-crystalline Casimir effect in the presence of a patterned substrate

F. Karimi Pour Haddadan·F. Schlesener·S. Dietrich
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Abstract

We consider a nematic liquid crystal confined by two parallel planar interfaces, one being laterally homogeneous and the other provided by a substrate endowed with a periodic chemical stripe pattern. Based on continuum theory we analyze the influence of the lateral pattern on the liquid-crystalline Casimir force acting on the interfaces of the nematic cell at distance d due to the thermal fluctuations of the nematic director. For d much larger than the pattern periodicity, the influence of the patterned substrate can be described by a homogeneous, effective anchoring energy. By tuning this parameter we recover previous results for the liquid-crystalline Casimir force. For the general case, i.e., smaller separations, we present new numerical results.

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F. Karimi Pour Haddadan, F. Schlesener, S. Dietrich. 2004-05-28. Liquid-crystalline Casimir effect in the presence of a patterned substrate. https://doi.org/10.1103/physreve.70.059901

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