Wavelength-tunable, linearly polarized Q-switched and gain-switched polarization-maintaining Er[formula omitted]-doped fluoride fiber laser in the range of 2.7[formula omitted]2.83 [formula omitted

Abstract

We demonstrate the ∼2.8 μm linearly polarized μs-scale pulse generation from a polarization-maintaining (PM) Er3+-doped fluoride fiber laser by Q-switching and gain-switching, for the first time to our knowledge. The achieved pulses have a polarization extinction ratio (PER) of up to ∼23 dB, and a repetition rate of several to tens of kHz with a maximum average power of hundreds of mW. By introducing a ruled reflective diffraction grating into the cavity, the wavelengths are able to be continuously tuned in the spectral range of 2.7∼2.83 μm. This work represents the first report on a linearly polarized short pulse PM fiber laser in the mid-infrared, opening up new opportunities for some specific applications (e.g., frequency doubling, optical parametric oscillation, coherent combining).