Charge compensating defects study of YbF3-doped BaF2 crystals using dielectric loss

YbF-doped BaF crystals with various concentrations of YbF (0.05, 0.1, 0.17, 0.2 mol) have been grown using the conventional Bridgman method. Dielectric relaxation is used to study the charge compensating defects in BaF crystals with low YbF concentration. The optical absorption spectra reveal the existence of both Yb (in UV domain) and Yb (in IR domain) ions. In the investigated temperature range (150–320 K) we have observed only one type of dielectric relaxation. This relaxation with activation energy eV is associated with trigonal-type () centers. The charge compensating defects are discussed while taking also into account the optical absorption spectra and the calculated number of NNN dipoles whose relaxation is observed.