On-chip two-octave supercontinuum generation by enhancing self-steepening of optical pulses

TL;DR

This paper demonstrates through simulation that on-chip silicon nitride waveguides can generate an ultra-wide two-octave supercontinuum by enhancing self-steepening effects, overcoming dispersion challenges for integrated photonics.

Contribution

It introduces a novel approach to achieve two-octave supercontinuum generation on-chip by enhancing self-steepening in near-zero dispersion silicon nitride waveguides.

Findings

Achieved flat, low dispersion in silicon nitride slot waveguides over 500 nm.

Generated a two-octave supercontinuum from 630 to 2650 nm via enhanced self-steepening.

Formed an optical shock as short as 3 fs enabling ultra-wide-band applications.

Abstract

Dramatic advances in supercontinuum generation have been made recently using photonic crystal fibers, but it is quite challenging to obtain an octave-spanning supercontinuum on a chip, partially because of strong dispersion in high-index-contrast nonlinear integrated waveguides. We show by simulation that extremely flat and low dispersion can be achieved in silicon nitride slot waveguides over a wavelength band of 500 nm. Different from previously reported supercontinua that were generated either by higher-order soliton fission in anomalous dispersion regime or by self phase modulation in normal dispersion regime, a two-octave supercontinuum from 630 to 2650 nm (360 THz in total) can be generated by greatly enhancing self-steepening in nonlinear pulse propagation in almost zero dispersion regime, when an optical shock as short as 3 fs is formed, which enables on-chip ultra-wide-band applications.