Non-relaxor responses of highly ordered Pb(Sc1/2Nb1/2)O3 crystals
Abstract
Pb(Sc1/2Nb1/2)O3 crystals have been grown by the top seeded solid solution technique and present a pure rhombohedral perovskite structure. The existence of superlattices and calculations of the chemical order parameter confirm the high order degree of ion occupancy. Unlike previous reports, where Pb(Sc1/2Nb1/2)O3 takes on typical relaxor behavior, here it exhibits non-relaxor ferroelectric behavior. The domain structure appears full extinction under crossed polarizers when the temperature is slightly higher than the Curie temperature (68 °C), the field of crossed polarizers appears full dark, showing non-relaxor ferroelectric phase transition behavior. The temperature dependence of the dielectric permittivity shows a sharp peak around 70 °C without any trace of relaxor behavior. The coercive field and remnant polarization sharply drop down to zero when the temperature is higher than 68 °C.