Abstract:
Processes of the polarization switching in ceramic relaxors PPb(Mg$_{1/3}$Ti$_{1/3}$W$_{1/3}$)O$_3$, Pb(Mg$_{1/4}$Sc$_{1/4}$Nb$_{1/4}$W$_{1/4}$)O$_3$, Pb(Mg$_{1/5}$Sc$_{1/5}$Ti$_{1/5}$Nb$_{1/5}$W$_{1/5}$)O$_3$, and Pb(Mg$_{1/6}$Sc$_{1/6}$Ti$_{1/6}$Sn$_{1/6}$Ta$_{1/6}$W$_{1/6}$)O$_3$ have been investigated at frequencies from 50 Hz to 2 kHz in the temperature range 90–300 K for measuring field amplitudes up to 20 kV/cm. It has been demonstrated that, under specific conditions, these materials are characterized by saturated dielectric hysteresis loops, which indicate the appearance of the ferroelectric state induced by the electric field. The dependences of the spontaneous polarization and the coercive field of the relaxors under investigation on their chemical composition, temperature, and frequency of the measuring voltage have been determined.