Spectroscopy, gain and laser operation of Tm-doped monoclinic crystals KY(WO/sub 4/)/sub 2/ and KYb(WO/sub 4/)/sub 2/

Summary form only given. Spectroscopic measurements and a study of laser operation of monoclinic crystals KY(WO/sub 4/)/sub 2/:Tm and KYb(WO/sub 4/)/sub 2/:Tm have been performed. Under laser pumping of 800 nm, the room temperature threshold of 70 mW and slope efficiency of 45 percent have been demonstrated for a 1 mm thick crystal plate of KY(WO/sub 4/)/sub 2/:Tm. Preliminary results show that the tuning range may extend over /spl sim/1850 to /spl sim/1950 nm. The most important results of our study (the lifetime of 3F4 manifold /spl tau//sub 2/ the peak emission cross-section /spl sigma//sub eff//sup max/, the upconversion coefficient k/sub /spl Sigma/Tm,/ the saturation intensity l/sub 0/ and others) are summarized for the same values of that of the well studied Tm:YAG crystals.