Influence of Li~+and Na~+Ions on the DielectricSpectra of YbF_3Doped and LiF, NaF CodopedCaF_2Crystals

摘要

Various concentrations YbF_3-doped CaF_2and Li- (Na)- codoped crystals were grownusing the conventional Bridgman method. The effect of Na~+and Li~+ions on the dielectric spectrawas studied. The ctivation energy and the reciprocal frequency factor have been calculated inorder to characterize the observed relaxations. An anomaly of el behavior (not reported before)has been observed which is assigned with a phase transition of the order-disorder type.