Optical properties of Er3+ ions in transparent glass ceramics

A study of optical properties and upconversion processes among Er3+ ions in oxyfluoride glass and glass ceramic matrix has been carried out. From opti cal absorption spectra, the oscillator strengths have been obtained for sev eral transitions and they have been used to calculate the Judd-Ofelt parame ters. Experimental lifetime values are compared with those obtained with th e Judd-Ofelt theory. Different upconversion emissions at 545, 660 and 800 n m have been obtained in Er3+ doped glass and glass ceramics by exciting at 975 nm. A systematic investigation of the green upconversion is reported wi th the purpose of determining the involved upconversion mechanisms. (C) 200 1 Published by Elsevier Science B.V.