Critical behavior in a field for ferroelectrics near the Lifshitz point

Abstract

Abstract The results of the studies of the influence of a constant electric field, directed along the spontaneous polarization axis, on the temperature behaviour of the dielectric constant of the proper uniaxial ferroelectric Sn2P2S6, bears witness to the proximity of the second-order ferroelectric phase transition (PT) to the tricritical point. They also confirm the dependence of the Lifshitz point coordinates in the mixed S2P2(Se&x)6 crystal phase diagram on the degree of non-equilibrium of the electron subsystem in these semiconductors.