Ultrabroad supercontinuum generated from a highly nonlinear Ge-Sb-Se fiber

Abstract

We report the fabrication of a novel high nonlinear fiber made of Ge-Sb-Se chalcogenide glasses with high numerical aperture (∼1.0), where the core and the cladding glasses consist of Ge₁₅Sb₂₅Se₆₀ and Ge₁₅Sb₂₀Se₆₅ (mol. %), respectively. The nonlinear refractive index (n₂) of the core glass is 19×10^-18 m²/W at 1.55 μm, and its laser-induced damage threshold under irradiation of 3.0 μm fs laser is approximately 3674 GW/cm². By pumping a 20-cm-long fiber with a core diameter of 23 μm using 150 fs pulses at 6.0 μm, supercontinuum spanning from ∼1.8 to ∼14 μm was generated.