Supercontinuum generation in As2S3 waveguides fabricated without direct etching

We report a supercontinuum generation (SCG) in a waveguide that spontaneously forms without an etching process during the deposition of a core material on a preformed SiO2 substructure. The mechanism of dispersion control for this new, to the best of our knowledge, type of waveguide is analyzed by numerical simulation, which results in a design rule to achieve a target dispersion profile by adjusting the substructure geometry. SCG is experimentally demonstrated with a waveguide made of As2S3, chalcogenide glass, which has low material absorption over the mid-IR range. A dispersion-controlled waveguide with a length of 10 mm pumped with 77 pJ pulses at a telecommunication wavelength of 1560 nm resulted in a supercontinuum that extends by more than 1.5 octaves. (C) 2021 Optical Society of America

Automated summary

This study reports the supercontinuum generation in a waveguide formed on a preformed SiO2 substructure during the deposition of core material without an etching process. Numerical simulations were used to analyze the dispersion control mechanism, resulting in a design rule to achieve a certain dispersion profile. Experimental demonstration using a dispersion-controlled waveguide made of As2S3 showed successful supercontinuum generation extending over 1.5 octaves.