Widely wavelength tunable gain-switched Er3+-doped ZBLAN fiber laser around 2.8 μm

In this paper, we demonstrate a wavelength widely tunable gain-switched Er3+ doped ZBLAN fiber laser around 2.8 ae m. The laser can be tuned over 170 nm (2699 nm similar to 2869.9 nm) for various pump power levels, while maintaining stable mu s-level singlepulse gain-switched operation with controllable output pulse duration at a selectable repetition rate. To the best of our knowledge, this is the first wavelength tunable gainswitched fiber laser in the 3 mu m spectral region with the broadest tuning range (doubling the record tuning range) of the pulsed fiber lasers around 3 mu m. Influences of pump energy and power on the output gain-switched laser performances are investigated in detail. This robust, simple, and versatile mid-infrared pulsed fiber laser source is highly suitable for many applications including laser surgery, material processing, sensing, spectroscopy, as well as serving as a practical seed source in master oscillator power amplifiers. (C) 2017 Optical Society of America