Switching current measurements in Pb(Zn_1/3 Nb_2/3)O₃-PbTiO₃ relaxor ferroelectric single crystals

Switching current measurements have been carried out on relaxor ferroelectric single crystal-PZN, and the solid solution 0.86PZN-0.04PT and 0.91PZN-0.09PT for crystallographic directions [001] and [111]. The experiments showed the presence of two maximum points in the switching current for 0.86PZN-0.04PT and 0.91PZN-0.09PT that can be attributed to the co-existence of two phases. The switching time inverse shows a two-fold linear dependence on applied field for both [001] and [111]. This suggests that the polarization reversal in the relaxor systems is related to the mobility of the domains. The switching time in relaxor ferroelectric is long (millisecs) compared to the reported data on normal ferroelectric Barium titanate (microsecs). The switching time is dependent on the composition of the crystal along both [001] and [111]. Along [111], the switching time decreases as the PT component increases in the crystal while along [001], the switching time increases as the PT increases.