Topology and nematic ordering. II. Observable critical behavior

Abstract

This paper is the second in a pair treating a lattice model for nematic media. In addition to the familiar isotropic (I) and nematically ordered (N) phases, the phase diagram established in the previous paper (paper I) contains a new, topologically ordered phase (T) occurring at large suppression of topological defects and weak nematic interactions. This paper (paper II) is concerned with the experimental signatures of the proposed phase diagram. Specific heat, light scattering, and magnetic susceptibility near both the N-T and I-T transitions are studied and critical behavior is determined. The singular dependences of the Frank constants K1,K2,K3 and the dielectric tensor anisotropy Δε on temperature as T→TNT- are also found. © 1995 The American Physical Society.