Thulium fibre laser pumped mid-IR source

A simple scheme for efficient generation of mid-IR laser radiation is demonstrated. Using a 25 W thulium fibre laser to pump a Q-switched Ho:YAG laser 15.3 W of average output power is achieved with an M2 of 1.3. The holmium laser is used to pump a ZGP OPO generating 7.2 W of average output power in the 3-5 μm waveband with an M2 of 1.8.