G. Fanjoux | Searcharxiv

arXiv2026

Picosecond Supercontinuum Generation in All-Normal Dispersion Optical Fibers Enabled by Polarization Instabilities

Supercontinuum generation in all-normal-dispersion optical fibers has so far been predominantly explored under femtosecond pumping conditions. Here, we demonstrate that efficient and broadband supercontinuum generation can also be achieved in the long picosecond regime by pumping a highly birefringent all-normal-dispersion silica-based photonic crystal fiber at 1064 nm. The observed spectral broadening results from the combined action of polarization modulation instability and cascaded Raman scattering, enabling octave-spanning spectra extending from 600 nm to 1650 nm. These results establish a distinct operating regime for supercontinuum generation and open new perspectives for robust, high-power broadband fiber sources.

physics.optics↗

arXiv2024

Supercontinuum generation in high-index doped silica photonic integrated circuits under diverse pumping settings

Recent advances in supercontinuum light generation have been remarkable, particularly in the context of highly nonlinear photonic integrated waveguides. In this study, we thoroughly investigate supercontinuum (SC) generation in high-index doped silica glass integrated waveguides, exploring various femtosecond pumping wavelengths and input polarization states. We demonstrate broadband SC generation spanning from 700 nm to 2400 nm when pumping within the anomalous dispersion regime at 1200 nm, 1300 nm, and 1550 nm. In contrast, pumping within the normal dispersion regime at 1000 nm results in narrower SC spectra, primarily due to coherent nonlinear effects such as self-phase modulation and optical wave breaking. Additionally, we examine the impact of TE/TM polarization modes on SC generation, shedding light on the polarization-dependent characteristics of the broadening process. Moreover, Raman scattering measurements reveal the emergence of two new peaks at 48.8 THz and 75.1 THz in the Raman gain curve. Our experimental results are supported by numerical simulations based on a generalized nonlinear Schrodinger equation that incorporates the new Raman gain contribution. Finally, relative intensity noise measurements conducted using the dispersive Fourier transform technique indicate excellent stability of the generated SC spectra.

physics.optics↗