Watt-level supercontinuum generation in As2Se3 fibers pumped by a 2-micron random fiber laser

Abstract

Chalcogenide fibers are good candidates for generating supercontinuum (SC) radiation due to their large nonlinear refractive indices and high mid-infrared transmission, but their low damage thresholds hamper the SC power scaling, thereby limiting the ultimately achieved SC brightness. Here, we report an As2Se3 fiber SC system pumped by a novel random Q-switched 2 μm Tm3+ fiber laser. The maximum SC output power is 1.09 W with slope efficiency of 24%, and the SC spans from ~1980 to ~2500 nm with a spectral width of ~500 nm at the −20 dB points. The spectral power density is ~2 mW nm−1. To the best of our knowledge, this is the highest power and spectral density SC emission ever achieved in chalcogenide fibers.