New Crystalline Lasers on the Base of Monoclinic KR(WO₄)₂:Ln³⁺ Tungstates (R=Y and Ln)

Abstract

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 μm wavelength in the new lasing ¹D₂→³F₃ 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. 4f²-4f² 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 ¹D₂→³F₃ and ¹D₂→³F₄ channels are identified. In yttrium and gadolinium sensitized-tungstates a two-micron (³H₄→³H₆) low-threshold generation of Tm³⁺ ions at cryogenic temperatures is achieved.