Laser-induced lensing effects in solid-state optical refrigerators

Abstract

Laser-induced thermal and population lensing effects in solid-state optical refrigerator materials are quantitatively evaluated. Time-resolved lensing transients in Yb3+ doped ZBLAN and aluminosilicate glasses are measured, and the model decouples thermal and population lensing effects. The analysis yields the net power density, the cooling efficiency, and important photo-physical parameters. The respective values are in good agreement with previously reported parameters for ZBLAN glass. Aluminosilicate glass is found to be a promising optical refrigerator material. We show that the measurement of laser-induced lensing is a valuable tool that can advance the characterization and optimization of materials for cryogenic optical refrigerators.