Space-time observation of the dynamics of soliton collisions in a recirculating optical fiber loop

TL;DR

This study experimentally observes the space-time dynamics of soliton collisions in a recirculating optical fiber loop, confirming nearly-elastic interactions and pairwise shifts predicted by integrable nonlinear wave theory.

Contribution

First experimental visualization of multi-soliton interactions in a fiber loop, validating theoretical predictions of the inverse scattering transform for nearly-integrable systems.

Findings

Soliton collisions are nearly elastic with no velocity change.

Position shifts during collisions match numerical simulations.

Three-soliton interactions are governed by pairwise effects.

Abstract

We present experiments performed in a recirculating fiber loop in which we realize the single-shot observation of the space and time interaction of two and three bright solitons. The space-time evolutions observed in experiments provide clear evidence of a nearly-integrable nonlinear wave dynamics that can be easily interpreted within the framework of the inverse scattering transform (IST) method. In particular collisions between solitons are found to be almost perfectly elastic in the sense that they occur without velocity change and with only a position (time) shift quantitatively well described by numerical simulations of the integrable nonlinear Schr\"odinger equation. Additionally our experiments provide the evidence that the position (time) shifts arising from the interaction among three solitons are determined by elementary pairwise interactions, as it is well known in the IST theory.