| Abstract: | Conclusions It can be concluded from this review that ferroelectric physics is one of the actively expanding branches of solid-state physics. The concepts of states  related to the ferroelectric one, e.g., the ferroelastic state, have broadened significantly. Within this field successful studies are being performed of such general questions as phase transitions, subsystem interactions, i.e., the interaction of different quasiparticles, and other nonlinear processes. In ferroelectric semiconductors the interaction of charge carriers with spontaneous polarization is being studied, while in Seignette ferromagnetics the interaction of magnetic and electric subsystems is under investigation. Nonlinear phenomena are given special study in the phase transition region.A number of new interesting phenomena have been discovered in ferroelectric studies recently: phonon echo, photovoltaic effect, autolocalization of charge carriers in the phase transition region, etc. Many new classes of ferroelectrics have been discovered, thus demonstrating the broad extent of the ferroelectric state in nature. Apparently, certain organic compounds and liquid crystals may be classified as ferroelectrics. Results of ferroelectric studies are widely used in the national economy.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 1, pp. 5–39, January, 1979. |
