Six-Watt mid-infrared laser using harmonic generation with Tl3AsSe3

An output of 6 W at 30 kHz was achieved using Tl3AsSe3 as the nonlinear second-harmonic generator. It was pumped with a CO2 laser source at a wavelength of 9.25 mu m with 20 ns pulses, and the laser beam was focussed to a spot size of 150 mu m. The focussed spot was scanned to reduce the continuous-wave power loading, and the system could be operated for extended periods of time under these conditions.