Temporal Fresnel diffraction induced by phase jumps in linear and nonlinear optical fibres

TL;DR

This paper investigates how phase jumps in optical fibers influence temporal diffraction patterns, providing analytical and numerical insights into linear and nonlinear regimes, with implications for understanding complex optical interference phenomena.

Contribution

It introduces a comprehensive analytical framework for temporal Fresnel diffraction caused by phase jumps in fibers, including nonlinear effects, which was not previously detailed.

Findings

Analytical expressions for diffraction patterns are derived.

Nonlinear effects lead to the emergence of coherent structures.

The study connects diffraction phenomena with well-known optical interference patterns.

Abstract

We analytically and numerically study the temporal intensity pattern emerging from the linear or nonlinear evolutions of a single or double phase jump in an optical fiber. The results are interpreted in terms of interferences of the well-known diffractive patterns of a straight edge, strip and slit and a complete analytical framework is provided in terms of Fresnel integrals for the case of purely dispersive evolution. When Kerr nonlinearity affects the propagation, various coherent nonlinear structures emerge according to the regime of dispersion.