Spectral transformations in the regime of pulse self-trapping in a nonlinear photonic crystal

TL;DR

This paper investigates how femtosecond pulses interact with nonlinear photonic crystals, revealing spectral shifts and narrow or wide-band radiation within the band gap due to self-trapping effects.

Contribution

It demonstrates, through numerical simulations, the spectral features arising from pulse self-trapping in nonlinear photonic crystals, highlighting phenomena within the band gap.

Findings

Spectral shifts occur inside the photonic band gap.

Narrow-band and wide-band radiation are observed.

Spectral features depend on specific conditions of pulse interaction.

Abstract

We consider interaction of a femtosecond light pulse with a one-dimensional photonic crystal with relaxing cubic nonlinearity in the regime of self-trapping. By use of numerical simulations, it is shown that, under certain conditions, the spectra of reflected and transmitted light possess the properties of narrow-band (quasi-monochromatic) or wide-band (continuum-like) radiation. It is remarkable that these spectral features appear due to a significant frequency shift and occur inside a photonic band gap of the structure under investigation.