High temperature dielectric relaxation anomalies in Ca0.9Nd0.1Ti0.9Al0.1O3−δ single crystals

Abstract

We herein report dielectric studies on Ca_0.9Nd_0.1Ti_0.9Al_0.1O_3−δ single crystals grown by the optical floating zone technique in the temperature range from room temperature to 660 K. Two dielectric anomalies were observed at ∼436 K and 520 K, which correspond to relaxor-like behaviour due to Maxwell–Wagner relaxations and conduction relaxation associated with doubly ionized oxygen vacancies respectively. The presence of Ti³⁺ for charge carrier hopping and oxygen vacancies is confirmed by X-ray photoelectron spectroscopy analysis.