Optical Absorption Spectra of Er3+:LaF3 and ErCl3 · 6H2O

Abstract

The absorption spectra of Er3+:LaF3 and ErCl3 · 6H2O were investigated in the visible and ultraviolet regions at 4°K. Transitions to practically all of the J levels occurring at <50 000 cm−1 have now been observed. Theoretical analysis of the results including the effects of configuration interaction as expressed in both two- and three-body operators made possible a good correlation between calculated and observed free-ion level energies. Comparison of the levels observed in the crystal matrices with reported gaseous free-ion levels suggested some inconsistencies in the latter, but indicated that there is little change in the J-level structure in the 4f11 configuration when Er3+ is incorporated in the crystal lattices studied.