Structure and dielectric properties of niobium-rich potassium lithium tantalate niobate single crystals

The structure and lattice parameters of high quality niobium-rich potassium lithium tantalate niobate (K0.95Li0.05)(Ta1−xNbx)O3 (x=0.44–0.66) single crystals were determined by the X-ray powder diffraction technique. Dielectric properties were studied in the temperature range from 20 to 500 K. The transition temperatures were determined, and the Curie temperatures adjusted between 330 K and 480 K through the suitable selection of Ta-to-Nb ratio. The degree of relaxation (γ) has been estimated using the modified Curie–Weiss law. The (K0.95Li0.05)(Ta1−xNbx)O3 single crystals have also shown strong dc electric field dependent dielectric behavior, and high dielectric tunability (∼43%) for x=0.44.