Grating-free 2.8 μm Er:ZBLAN fiber chirped pulse amplifier

We report on a grating-free fiber chirped pulse amplifier (CPA) at 2.8 mu m for the first time. The CPA system adopted Er:ZBLAN fiber with large anomalous dispersion as the stretcher and germanium (Ge) rods as the compressor with a compact structure. High-energy picosecond pulses of 2.07 mu J were generated at the repetition rate of 100 kHz. Using highly dispersive Ge rods, the amplified pulses were compressed to 408 fs with a pulse energy of 0.57 mu J, resulting in a peak power of approximately 1.4 MW. A spectral broadening phenomenon in the main amplifier was observed, which was caused by the special gain shape of the Er:ZBLAN fiber amplifier in operation and confirmed by our numerical simulation. This compact fiber CPA system at 2.8 mu m will be practical and meaningful for application fields.

Automated summary

This study reports on a grating-free fiber chirped pulse amplifier at 2.8 μm for the first time. The system utilized Er:ZBLAN fiber and Ge rods to generate high-energy picosecond pulses with peak power approximately 1.4 MW. The spectral broadening phenomenon observed in the main amplifier is considered meaningful for practical applications in relevant fields.