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• Spectral properties and high-efficiency broadband laser operation of Tm:CYGA crystal at 2 μm were demonstrated. • The maximum continuous-wave output power of 1.43 W was obtained. • A 284.7 nm tuning coverage was realized with a BF. We report on spectral properties and a high-efficiency broadband laser operation of Tm:CaY 0.9 Gd 0.1 AlO 4 (Tm:CYGA) crystal. The polarized absorption and emission spectra, gain cross sections and fluorescence lifetime are systematically studied, presenting a broad absorption and emission spectra and thus a smooth gain band. Furthermore, under an absorbed pump power of 4.35 W, a maximum continuous-wave (CW) laser output power of 1.43 W at 1967.8 nm is obtained, corresponding to a slope efficiency of 42.2 %. The beam quality factors (M2) in X-axis and Y-axis are measured to be 1.011 and 1.027, respectively. A tunable Tm:CYGA laser with a tuning range of 284.7 nm from 1837.5 to 2122.2 nm is achieved employing a birefringent filter (BF). The results indicate that the Tm:CYGA crystal is an excellent laser medium for generating high-efficiency broadband CW laser, indicating its potential for ultrashort pulse generation in the 2-μm spectral range. [ABSTRACT FROM AUTHOR]

High-quality Dy:PbWO 4 crystal has been successfully grown by the Bridgman method. Fluorescence properties of the grown crystal at the yellow-light region were discussed. The absorption cross-section of Dy3+ ions at 454 nm was calculated to be 0.142 × 10−20 cm2, which corresponded to the transition from 6H 15/2 to 4I 15/2 level. Based on Judd-Ofelt theory, the J-O intensity parameters Ω t and the emission cross-section were calculated. The fluorescence lifetime of 4F 9/2 level was measured to be 193 μs. • Dy: PbWO 4 crystal was grown successfully by the Bridgman method. • Judd-Ofelt theory was used to analyze the spectral properties of Dy: PbWO 4 for the first time. • Dy: PbWO 4 crystal is a potential laser medium for yellow laser operation. [ABSTRACT FROM AUTHOR]