Spectroscopy and laser properties of Tm3+: KY(WO4)(2) crystal

The polarized absorption spectra of Tm3+-doped potassium yttrium tungstate (Tm:KY(WO4)(2)) crystal at room temperature were measured. The emission spectrum and lifetime of the F-3(4) excited state were determined. Using standard and modified Judd-Ofelt theories, the intensity parameters and the radiative lifetimes were calculated and good agreement with the experimental results was obtained for both theories. Continuous-wave laser operation in Tm:KYW crystal under laser diode pumping at 802 nm and 1750 nm was demonstrated with slope efficiency of 53% and 28% and output power of about 555 mW and 86 mW, respectively.