New crystalline lasers on the base of monoclinic KR(WO4)(2):Ln(3+) tungstates (R=Y and Ln)

Monoclinic KY(WO4)(2):Pr3+, Tm3+:KY(WO4)(2):Er3+, Yb3+ single crystals are grown by low-gradient Czochralski technique. Stimulated emission at 1.0223 mu m wavelength in the new lasing D-1(2) --> F-3(3) channel of Pr3+ ions in KY(WO4)(2) at room temperature under Xe-flashlamp pumping is excited. Full sets of Stark-level energies for Pr3+ ions in KY(WO4)(2) and KGd(WO4)(2) crystals at 77 K are determined. 4f(2)-4f(2) intensity-transitions for the KY(WO4)(2):Pr3+ are analyzed preliminarily. All observed at present and earlier one-micron Pr3+-ion, induced transitions in the D-1(2) --> F-3(3) and D-1(2) --> F-3(4) channels are identified. In yttrium and gadolinium sensitized-tungstates a two-micron (H-3(4) --> H-3(6)) low-threshold generation of Tm3+ ions at cryogenic temperatures is achieved.