Dysprosium thiogallate laser: source of mid-infrared radiation at 2.4, 4.3, and 5.4 µm

Various Dy:PbGa2S4 laser-active material energy transitions originating from the 6H9/2 + 6F11/2 or 6H11/2 energy level were investigated, and the mid-infrared radiation generation has been demonstrated. The Dy:PbGa2S4 laser was pumped by a 1.32-µm free-running Nd:YAG laser or laser diode radiation corresponding to the Dy:PbGa2S4 absorption peak. The Dy:PbGa2S4 crystal was placed in the stable optical resonator with the mirrors chosen according to the required generated wavelength. New laser wavelengths of 2.4 and 5.4 µm were generated from the Dy:PbGa2S4 laser at room temperature. Laser output characteristics at 4.3 µm are also presented.