High-efficiency 0.3 nm narrow spectral width Fe:ZnSe laser with output power of 32.9 W

We report on a widely tunable Fe:ZnSe laser pumped by Er:YSGG laser operating in the spectral range from 3.9 µm to 4.6 µm, with a narrow spectral width of 0.3 nm by using intracavity prisms and Fabry-Perot (F-P) etalons. Theoretical model describing the wavelength-dependent dynamic process of Fe:ZnSe laser was demonstrated, the highest average power of 32.9 W was obtained at 4.39 µm corresponding to an optical-to-optical efficiency of 28% and a slope efficiency of 34%, with the beam quality factor M²_x of 1.57 and M²_y of 1.52.