Dielectric Properties and Electron Paramagnetic Resonance of Nanocrystalline Potassium Tantalate

Dielectric constant, losses, and Electron Paramagnetic Resonance (EPR) spectra of the nanocrystalline potassium tantalate were obtained and investigated. In the temperature dependence of the dielectric constant, a wide peak in the interval 20 < T < 40 K was observed. Maximum value of epsilon is 390. This dielectric peak did not shift to higher temperature as the measuring frequency was increased from 25 Hz to 1 MHz. Dielectric losses have several low-temperature frequency-dependant peaks. Obviously, these peaks reflect the reorientation motion of the dipole centers in the material. EPR spectra of nanocrystalline potassium tantalate consist of two types of signals-a ferromagnetic and a paramagnetic signal.