High-temperature dielectric properties of Gd _2CuO _4 ceramics

摘要

A sample of Gd _2CuO _4 (GCO) has been prepared through the solid state reaction technique. Dielectric properties of this material have been measured in detail as functions of temperature (between 285 and 450 K) and frequency (20 Hz10 MHz). A step-like increase below 330 K and a broad peak around 360 K were observed in the real part of the permittivity (ε′) which were found to be originated from the oxygen vacancy hopping motions that cause a dipolar relaxation, followed by a MaxwellWagner relaxation as the hopping carriers are blocked by the interfaces and surfaces of the sample.