Light bullets by synthetic diffraction-dispersion matching

TL;DR

This paper introduces a novel method for creating stable three-dimensional light bullets by matching material dispersion with effective diffraction in waveguide arrays with periodic refractive index modulation.

Contribution

The work demonstrates a new technique using out-of-phase longitudinal modulation to tune diffraction, enabling light bullet formation at lower energies than previously possible.

Findings

Stable 3D light bullets can be generated with reduced energy levels.

Effective diffraction can be precisely matched to material dispersion using waveguide arrays.

The approach broadens the conditions under which light bullets can be formed.

Abstract

We put forward a new approach to generate stable, fully three-dimensional light bullets, which is based on the matching of the intrinsic material dispersion with a suitable effective diffraction. The matching is achieved in adequate waveguide arrays whose refractive index is periodically modulated along the direction of light propagation. We show that by using non-conventional, out-of-phase longitudinal modulation of the refractive index of neighboring channels, it is possible to tune the effective diffraction to match the intrinsic material group velocity dispersion. Three-dimensional light bullets are shown to form at reduced energy levels, in settings where the dispersion would be far too weak to generate bullets in the absence of array.