Electrical properties of 0.90Pb[(Mg,Zn) 1/3Ta 2/3] O 3-0.10PbTiO 3 relaxor

Abstract

Polycrystalline 0.90Pb[(Mg2/3Zn1/3)(1/3)Ta-2/3]O-3-0.10PbTiO(3) having a tetragonal perovskite type structure was prepared by the high temperature solid-state reaction method. Dielectric studies showed the relaxor behaviour with a diffuse phase transition. A high value of e max (> 10 000) was achieved with the temperature T-m of maximum permittivity around room temperature at 1 kHz. The frequency dependence of Tm was modelled using the Vogel-Fulcher law. The dielectric relaxation in the material investigated here was found to be analogous to the magnetic relaxation in a spin-glass system. The shape of the complex impedance curve indicated that the system exhibited almost the Debye type dielectric relaxation at 350 degrees C, where as a non-Debye profile was observed at temperatures below 325 degrees C. Furthermore, the relaxation frequency was found to shift towards higher frequencies upon increasing temperature.