Phase transitions and domain structures in relaxor-based ferroelectric (PbZn1/3Nb2/3O3)0.915(PbTiO3)0.085 single crystal

Abstract

Polarization-electric field (P-E) hysteresis loops and domain structures have been measured as a function of temperature in relaxor-based ferroelectric single crystal (PbZn,/3Nb2/303)0.9~j(PbTi03)o.o~s (PZN-8.5%PT). In order of increasing temperature, PZN- 8.5%PT undergoes successive phase transitions: rhombohedra1 phase (below -375 K) + coex- istence of rhombohedral and tetragonal phases (between -375 and -390 K) --f tetragonal phase (between -390 and -420 K) -+ coexistence of tetragonal and cubic phases (between -420 and -460 K) -+ cubic phase (above -460 K). Phase coexistence suggests an inhomogeneous distribution of Ti4+ concentration in the PZN-8.5%PT crystal.