Mid-infrared supercontinuum generation in a fluoroindate fiber with 1.4 W time-averaged power

A mid-infrared supercontinuum generation in a step-index fluoroindate fiber pumped by a Tm-doped fiber amplifier seeded with 1.55 µm pulses is reported for the first time. By pumping a 9 µm core fluoride fiber with 3.7 W of power, a broadband supercontinuum with a total output power of 1.41 W and a spectrum extending to 4.1 µm was demonstrated. It is believed that this is the broadest mid-infrared supercontinuum spectrum with Watt-level time-averaged power generated out of a fluoroindate fiber. The impurities incorporated in the fiber are identified as the main limitation in terms of output power scaling up. (letter)