4 μm HBr Fiber Gas Laser

摘要

We report here a 4 μm fiber laser in HBr-filled silica hollow-core fibers (HCFs). Pumped by a 2 urn thulium-doped fiber amplifier (TDFA), a maximum 4 μm power of ~350 mW is achieved with a conversion efficiency of about 10%. Furthermore, this system could be extended to generate widely tunable wavelength range up to 4.5 μm by using a small-range tunable 2 μm pump fiber laser, which will open a new opportunity for mid-IR fiber lasers. © 2020 The Author(s)