Generation of 35 kW peak power 80 fs pulses at 29 μm from a fully fusion-spliced fiber laser

Tunable femtosecond light sources in the short wave and middle wave infrared regions are of utmost importance for various applications ranging from multiphoton microscopy, mid-infrared supercontinuum generation to high-harmonic generation. We report on an all-fusion-spliced fiber laser emitting 80 fs pulses up to 2.9 μm with 35 kW peak power. The laser is based on Raman self-frequency shift effect from 1560 nm up to 3000 nm in germanium-doped fibers fabricated by the widespread modified chemical vapor deposition process.