Transição por redução de camadas em filmes esméticos livremente suspensos nas proximidades de transição SmA-N

Abstract

In the present work, we studied how surface effects and the presence of an external field modify the properties of smectic films. Initially, we investigated the transition by reducing layers in a regime of the parameter α that corresponds to the neighborhood of the smectic-A-nematic phase transition (SmA − N). By using the McMillan-Mirantsev Model for smectic order, where we solve the self-consistent relationships that define the parameters of the nematic order s and smectic σ that minimized the free energy of Helmolthz. We demonstrated that a layer thinning induced by an external field, can occur in smectic films with negative anisotropy even below the Bulk transition temperature . We also investigated the profiles of fluctuations in the smectic order.