Dielectric and ionic conduction properties in LiYF4 single crystals

A LIYF4 single crystal was grown by the Czochralski technique in an Ar-gas atmosphere. The complex dielectric constants and complex impedances are measured in the range of 100 Hz-10 MHz and up to 200 degrees C for a c-plate of a LiYF4 single crystal. The LiYF4 reveals a strong low frequency dielectric dispersion below 300 kHz, from room temperature to 200 degrees C. It is believed that the strong dielectric dispersion is related to the ionic hopping conduction, which arises mainly from the jumping of Li+-ions between neighboring sites, with an activation energy of Delta = 0.49 eV. The conduction mechanism seems to be the non-interacting Debye type and the relaxation times satisfy the Arrhenius relation. (C) 2000 Elsevier Science Ltd. All rights reserved.