On the possibility of mid-IR supercontinuum generation in As-Se-Te/As-S core/clad fibers with all-fiber femtosecond pump source

Abstract

We propose and optimize theoretically a supercontinuum (SC) laser source in the mid-IR based on using As-Se-Te/As-S core/clad step-index fibers and a femtosecond all-fiber laser system at 2μm. Numerically simulated spectra extending from ~1μm to >8μm are demonstrated for pump energy of order 100pJ in a fiber with a core diameter of 2μm. To the best of our knowledge, the possibility of such long-wavelength spectral conversion of pump pulses at the wavelength of 2μm in optical fibers is demonstrated for the first time. The theoretical calculations are performed on the base of real low loss step-index As-Se-Te/As-S glass fibers with various core-clad diameter ratios.