Generation of 85 fs mid-IR pulses with up to 2.4 W average power using an Er:ZBLAN fiber mode-locked oscillator and a nonlinear amplifier

In this paper, we report a high power and compact mid-IR ultrafast laser system consisting of an Er:ZBLAN fiber-based mode-locked oscillator and a nonlinear amplifier. The mode-locked pulses are amplified and simultaneously nonlinearly compressed to sub-100 fs, without using any external pulse compressor or dispersion-managing stretcher. The output pulses have ∼85 fs pulse durations at ∼2.85 µm, with an average power of up to 2.4 W, and pulse energies of >40 nJ. This constitutes the highest average power sub-100fs duration pulses generated from a mid-IR fiber laser system to date.