Dielectric properties of ferroelectric Rb2CoBr4

Abstract Single crystals of Rb2 CoBr4 were grown by the Bridgman method. DTA and the dielectric constant measurements revealed that the normal-incommensurate transition point T i is 60°C and the lock-in transition (Curie temperature T c) is—81°C (on heating). The temperature dependence of spontaneous polarization P s, coercive field E c, and antiferroelectric polarization P AF were measured for a single-crystal sample down to liquid nitrogen temperature.