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

摘要

Dramatic advances in supercontinuum generation have been made recently usingphotonic crystal fibers, but it is quite challenging to obtain anoctave-spanning supercontinuum on a chip, partially because of strongdispersion in high-index-contrast nonlinear integrated waveguides. We show bysimulation that extremely flat and low dispersion can be achieved in siliconnitride slot waveguides over a wavelength band of 500 nm. Different frompreviously reported supercontinua that were generated either by higher-ordersoliton fission in anomalous dispersion regime or by self phase modulation innormal dispersion regime, a two-octave supercontinuum from 630 to 2650 nm (360THz in total) can be generated by greatly enhancing self-steepening innonlinear pulse propagation in almost zero dispersion regime, when an opticalshock as short as 3 fs is formed, which enables on-chip ultra-wide-bandapplications.