Mid-IR supercontinuum generation in thulium-doped fiber amplifier

At present long wavelength limit for supercontinuum generation in the silica based fibers was shown [1, 2]. Also one of the interesting problems is to obtain the high spectral power density. One of the ways to get it is using optical fiber amplifiers as a media for supercontinuum generation. Yb-doped fiber amplifier was used for supercontinuum generation [3], but longest wavelength generation was above 2 um. To enhance supercontinuum spectrum in the range over 2 um one should use fibers doped by thulium or holmium as gain media [4, 5].