Extreme polarization-dependent supercontinuum generation in an uncladded silicon nitride waveguide

We experimentally demonstrate the generation of a short-wave infrared supercontinuum in an uncladded silicon nitride (Si3N4) waveguide with extreme polarization sensitivity at the pumping wavelength of 2.1 mu m. The air-clad waveguide is specifically designed to yield anomalous dispersion regime for transverse electric (TE) mode excitation and all-normal-dispersion (ANDi) at near-infrared wavelengths for the transverse magnetic (TM) mode. Dispersion engineering of the polarization modes allows for switching via simple adjustment of the input polarization state from an octave-spanning soliton fission-driven supercontinuum with fine spectral structure to a flat and smooth ANDi supercontinuum dominated by a self-phase modulation mechanism (SPM). Such a polarization sensitive supercontinuum source offers versatile applications such as broad-band on-chip sensing to pulse compression and few-cycle pulse generation. Our experimental results are in very good agreement with numerical simulations. (C) 2021 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

Automated summary

The experimental demonstration in an uncladded silicon nitride waveguide achieves the generation of a short-wave infrared supercontinuum with extreme polarization sensitivity, allowing for polarization mode switching and obtaining experimental results that are in very good agreement with numerical simulations.