Soft modes in confined nematic liquid crystals

Collective fluctuations of the liquid-crystalline order in two model geometries with a domain-like equilibrium configuration are analyzed within the Landau-de Gennes theory. The wetting-induced heterophase structure is characterized by a localized soft mode corresponding to fluctuations of the position of the interface between the tare phases. In a very thin hybrid cell, the soft mode is associated with a structural transition from the configuration with a step-like profile of the tilt angle to the usual bent structure. Thin slowdown is exhibited by the lowest director mode. In both geometries the critical behavior is expected to be observable by the evanescent light wave scattering.