Investigation of intrinsic defect structure in 0.91Pb(Zn1/3Nb2/3)O3-0.09PbTiO3 single crystal through AC conductivity

Complex impedance spectroscopy study was done on 0.91Pb(Zn1/3Nb2/3)O-3-0.09PbTiO(3) (PZN-PT) single crystals in the wide range of temperatures (25-525degreesC) and frequencies (I kHz-1 MHz). The ac conductivity was computed from the impedance data and the activation energy for conduction at different frequencies was determined. Frequency explicit plots of imaginary components of impedance exhibit Debye-like peak shapes. Cole-Cole diagrams were observed in the high temperature regime. Temperature dependent conductivity measurement and Cole-Cole plots fairly establish the existence of quenched random defects in the PZN-PT system.