3.5kW coherently combined ultrafast fiber laser

We present a coherently-combined ultrafast fiber laser system consisting of four amplifier channels delivering 3.5 kW average power at 80 MHz repetition rate with a pulse duration of 430 fs FWHM and a close-to-diffraction-limited beam quality with an M2 < 1.2. The system incorporates a fully automated self-adjustment of the beam combination, allowing for a quasi-turn-key operation of the system. At the date of publication, this system delivers the highest average power reported from an ultrafast laser.