Basic optical absorption of Er in Bi2TeO5 single crystals

Abstract The basic absorption spectra of Er in Bi 2 TeO 5 crystals are presented and analyzed. Eight transitions were identified from the 4 I 15/2 ground state with all the possible Stark components at 10 K. Further splitting of the lines indicated three major sites for Er 3+ in the crystal. Transitions from the higher Stark levels of the ground state were identified at 200 K. The spectroscopic observations are in good agreement with previous results on oxide crystals exhibiting similar coordination number and symmetry.