Long-term stable 120W fiber CPA with 1.3GW peak power at 2µm

We present the first high-power coherently combined thulium-doped fiber-CPA. The laser system delivers >228 µJ pulse energy with 48 hours of operation even at an average-power >120 W. The simultaneous availability of 100 W class average power and 1 GW-class peak power in the 2 µm wavelength regime is not only unique in the world of science but also comes in a fully engineered and commercially available system design optimized for long-term operation..