2018/04/20 by Maes, Frédéric, Fortin, Vincent, Poulain, Samuel +4
#FOS: Physical sciences #Optics (physics.optics)
paper · doi:10.48550/arxiv.1804.08610
Rare-earth-doped fiber lasers are promising contenders in the development of spectroscopy, free-space communications and countermeasure applications in the 3 - 5 μm spectral region. However, given the limited transparency of the commonly used fluorozirconate glass fiber, these systems have only achieved wavelength coverage up to 3.8 μm, hence fueling the development of more suitable fiber glass compositions. To this extent, we propose in this Letter a novel heavily holmium-doped fluoroindate fiber, providing extended transparency up to 5 μm, to demonstrate the longest wavelength room temperature fiber laser at 3.92 μm. Achieving ≈ 200 mW of output power when cladding pumped by a commercial 888 nm laser diode, this demonstration paves the way for powerful mid-infrared fiber lasers emitting at and beyond 4 μm.