Towards new lasers in Ti:Er:LiNbO3 waveguides:: a study of the excited Er3+ states

Detailed excited state absorption measurements under pumping at 980 nm and 1.5 mu m together with conventional absorption and emission spectroscopy is employed to investigate optical transitions of Er3+ in Ti:LiNbO3 channel-waveguides, The experimental data were evaluated using the Judd-Ofelt method giving parameters close to those in the bulk. The good agreement between theoretical prediction and measurements allows us to calculate cross section, lifetimes, and branching ratios. Based on these results we developed and tested a model which is able to predict the conditions for which laser operation at 550 nm and 2.7 mu m will be possible under 980 nm pumping.