Growth, structure and spectroscopic properties of Er,Pr:YAP laser crystal.

Abstract Er3+ and Pr3+ co-doped YAP laser crystal with high optical quality was grown successfully by the Czochralski method for the first time. By contrast, an Er3+ single doped YAP laser crystal was also grown. The cell parameters of the two crystals were obtained by the X-ray Rietveld refinement method. The X-ray rocking curves indicate that the as-grown crystals possess excellent crystalline quality. The absorption spectra show that the crystals are suitable to be pumped by 972 nm LD. The NIR and MIR emission spectra, the up–conversion spectra and the fluorescence decay curves were also measured to investigate the influence of Pr3+ ions on the spectroscopic properties. The results indicate the Pr3+ ions acting as the deactivator can decrease efficiently the lifetime of the lower laser level 4I 13/2 of the Er3+ ions from 10.72 to 0.489 ms, which would be beneficial to decrease the laser threshold and increase the laser conversion efficiency. Highlights • XRCs show Er:YAP and Er,Pr:YAP crystals possess high crystalline quality. • Pr3+ deactivator reduces 4I 13/2 lifetime from 10.72 to 0.489 ms, benefiting to decrease threshold and improve efficiency. • NIR and UC fluorescence provide further evidence that Pr3+ ions can efficiently depopulate Er3+ ions at 4I 13/2 level. • All results indicate the Er,Pr:YAP crystal is a promising laser medium for realizing a 2.7 μm laser pumped by 970 nm LD. [ABSTRACT FROM AUTHOR]