Comparative study of the optical spectra of Er3+ in Er2BaCuO5 and Er2BaZnO5

Optical absorption spectra of the two compounds Er2BaZnO5 and Er2BaCuO5 hav ing the same crystallographic structure of the 'green phase' have been meas ured in a wide spectral range. The spectra of both compounds are similar, w hich points to a similarity of the crystal field around the erbium ion. The crystal field is, however, somewhat stronger for the copper compound. The calculations have been performed using the crystal field parameters obtaine d earlier for the two sites of Eu3+ in Y2BaZnO5. The calculated overall spl ittings of J-manifolds and the distribution of levels are in agreement with the experiment. The high-resolution infrared spectra of Er2BaZnO5 revealed a fine structure of absorption lines which has been attributed to the Davy dov splitting, (C) 1999 Elsevier Science B.V. All rights reserved.