High-efficiency broadly tunable Cr:ZnSe single crystal laser pumped by Tm:YLF laser

A high-efficiency broadly tunable Cr:ZnSe single crystal laser longitudinally pumped by a continuous-wave (CW) Tm:YLF laser at 1918 nm is demonstrated. To our best knowledge, a laser based on a Cr:ZnSe single crystal grown by the temperature gradient technique (TGT) method is investigated here for the first time. Under an incident pump power of 3.5 W, a maximum 383 mW CW output power was obtained at 2391 nm, corresponding to a slope efficiency of 10.6%. Furthermore, the working wavelength can be continuously tuned from 2179 to 2720 nm by means of an intracavity Brewster-cut CaF2 prism. (letter)