Production and Laser Characteristics of Fe 2+ :ZnS x Se 1− x Polycrystals

A method is developed for producing active laser elements (spectrum range 4 to 5 μm) based on polycrystalline solid solutions ZnSxSex-1 doped with iron ions. Bilateral diffusion doping of the elements by Fe2+ ions is performed during hot isostatic pressing. Spectral and energy characteristics of the laser are investigated with the Fe2+:ZnS0.1Se0.9 active element kept at room temperature. It is found that the absorption band of the Fe2+:ZnS0.1Se0.9 crystal is blueshifted with respect to the Fe2+:ZnSe absorption band, while the lasing spectra of the Fe2+:ZnSe and Fe2+:ZnS0.1Se0.9 lasers and their energy parameters are almost identical. The lasing energy of 580 mJ is obtained at the slope efficiency with respect to the absorbed energy of 46%. Further increase in the lasing energy is limited by development of transversal parasitic oscillation at a large size of the pump beam spot.