Phase transition in the vicinity of Lifshitz point in ferroelectrics-semiconductors

Abstract

The types of the critical behaviour of heat capacity. susceptibility and order parameter in the vicinity of the phase transition of the II order. tricritical point. Lifshitz point in ferroelectrics-semiconductors are discussed. including effects of dimensionality, dipole-dipole long-range forces, defects and fluctuations. The experimental results for critical behaviour of dielectric susceptibility in uniaxial ferroelectric Sn2P2S6 in the vicinity of the II order phase transition which is close to multicritical points are presented and compared with the predictions of the theory.