The Study On Growth And Laser Properties Of Ho³⁺ Doped Self-Activated KYb(WO₄)₂ Laser Crystal

Potassium ytterbium tungstate [KYb(WO4)2], is a new self-activated laser crystal. The absorption wavelength of KYb(WO4)2 crystal is in a range of 930-980 nm. Absorption energy can couple with InGaAs LD. The study on KYb(WO4)2 is less, and there has no report about Ho:KYb(WO4)2 laser crystal.In this dissertation, Ho:KYb(WO4)2 crystal grown by Top Seeded Solvent Growth (TSSG) method, using K2W2O7 as flux. XRD analysis shows that Ho:KYb(WO4)2 is monoclinic system with space group C2/c. The infrared spectrum and Raman spectrum of the crystal was measured, the vibration modes were analyzed. The absorption spectrum of Ho:KYb(WO4)2 crystal was measured, the peak of Yb3+ at 935 and 987nm were found the strongest, FWHM reached 91 nm; the peak of Ho3+ at 1965nm was found the strongest, FWHM reached 135 nm. The fluorescence spectrum of the crystal was measured, the strongest emitting wavelength of Ho3- was at 1990nm and FWHM reached 71 nm. The laser behavior of the crystal was measured, we have obtained laser with an output power of 134.7mW TEMoo, an optical-to-optical conversion efficiency of 13.4% and a slope efficiency is no less than 33%. The output power of 7.5mW is obtained by quasi-CW pumped.