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arXiv · 1310.8501

Pseudo-Casimir interactions across nematic films with disordered anchoring axis

Fahimeh Karimi Pour Haddadan·Ali Naji·Azin Kh. Seifi·Rudolf Podgornik
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Abstract

We consider the effective pseudo-Casimir interaction forces mediated by a nematic liquid-crystalline film bounded by two planar surfaces, one of which imposes a random (disordered) distribution of the preferred anchoring axis in the so-called easy direction. We consider both the case of a quenched as well as an annealed disorder for the easy direction on the disordered surface and analyze the resultant fluctuation-induced interaction between the surfaces. In the case of quenched disorder, we show that the disorder effects appear additively in the total interaction and are dominant at intermediate inter-surface separations. Disorder effects are shown to be unimportant at both very small and very large separations. In the case of annealed disorder its effects are non-additive in the total inter-surface interaction and can be rationalized in terms of a renormalized extrapolation length.

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Fahimeh Karimi Pour Haddadan, Ali Naji, Azin Kh. Seifi, Rudolf Podgornik. 2013-10-31. Pseudo-Casimir interactions across nematic films with disordered anchoring axis. https://arxiv.org/abs/1310.8501

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