Thulium fibre laser pumped mid-IR laser

摘要

A simple scheme for efficient generation of mid-IR laser radiation is reported. Using a 50 W thulium fibre laser to pump a Q-switched Ho:YAG laser 27.3 W of average output power is achieved with an M~(2) of 1.5 (optical to optical conversion efficiency 65percent) at a wavelength of 2.1 (mu)m. The holmium laser is used to pump a ZGP OPO generating 12.6 W of average output power in the 3-5 (mu)m waveband (optical to optical conversion efficiency 52percent) with a worst case M~(2) of 2.7. These efficiencies were maintained at 25percent and 50percent duty cycle operation.