Picosecond Pulse Generation from a Wavelength Tunable Er:ZBLAN Mid-Infrared Fiber Laser

The ongoing research on mid-infrared lasers is motivated by their numerous applications, which include sensing, surgical procedures, and spectroscopy [1] . Current advancements in fluoride fiber-based radiation sources showcases their ability to provide extremely wide (exceeding 500 nm) tuning capabilities [2] , and generation of few-cycle pulses [3] . In the last years, frequency-shifted feedback mechanism has played a significant role in the development of short-pulse mid-infrared fiber lasers. It is a recently rediscovered approach to picosecond pulse generation that was successfully adapted to the ~3 µm spectral range, where availability of real saturable absorbers commonly used in near-infrared fiber lasers is still limited.