Pseudo-Casimir force in chiral smectic liquid crystals.
We present a theoretical study of the pseudo-Casimir force in two chiral smectic systems: a homeotropic cell and a free-standing film. We consider the interaction induced by the fluctuations of orientational order. We demonstrate how the character of the force depends on the type of fluctuation modes and on boundary conditions. We focus on the temperature dependence of the force, which is marked by the vicinity of the smectic-A*-->smectic-C* phase transition. We find that at this transition the force diverges if the system is frustrated; otherwise it remains finite. We expose the analogy between the force in these smectic systems and in previously studied nematic systems, thus demonstrating the universality of the pseudo-Casimir interaction.
Markun
B
B
Department of Physics, University of Ljubljana, Jadranska 19, SI-1000 Ljubljana, Slovenia. bostjan@fiz.uni.lj.si
Zumer
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S