Diode-end-pumped Tm:GdVO4 laser operating at 1818 and 1915 nm

High power operation at 1818 and 1915 nm has been demonstrated from a Tm:GdVO4 laser operating in quasi-continuous-wave mode with a maximum measured power of 8.7 W and a laser output energy of 175 mJ was observed in a 20 ms pulse at 1.9 mu m. The operation at 1818 nm is the shortest wavelength achieved at multi-watt power levels for a Tm-doped solid-state laser without intra-cavity tuning elements. It has been shown that by careful analysis of the emission spectra, the Tm:GdVO4 laser can be tuned over a 100 nm wavelength range simply by appropriate selection of the reflectivity of the output coupler.