Measurement and analysis of upconversion rates of Er:YAG at room temperature

We have measured upconversion fluorescence resulting from the excitation of room temperature 1% and 5% Er:YAG by a 1532 nm nanosecond pump source. Measurements of the fluorescence decay from the 4I13/2, 4I11/2, 4F9/2 and 4S3/2 manifolds to the 4I15/2 ground state manifold were observed over a wide range of excitation pulse fluence values. A unique set of upconversion parameters were extracted from the measurements using a modification of the traditional rate equation model. Results of calculation are compared to measurement.