Thermally stimulated depolarization current studies in sodium- and barium-doped potassium yttrium fluoride

Abstract

The results of thermally stimulated depolarization current (TSDC) and electrical conductivity studies of potassium yttrium fluoride (KYF4) compound doped with sodium and barium are presented. The TSDCs were measured as a function of the polarizing temperature and polarizing field strengths at a constant heating rate of 0.09 K s−1. The conductivity studies were carried out in the temperature range 370–835 K with different dopant concentrations. The variation of the conductivity with the doping concentration was found to be non-linear. The relaxation parameters and the activation energies were evaluated. The origin of the TSDC peak in KYF4:Na was attributed to space charge polarization. However, in the case of KYF4:Ba, in addition to space charge polarization, there is also a small contribution from the dipolar mechanism.