Optics

Physics

Modulational instability

Dissipation

Nonlinear system

Perturbation (astronomy)

Optical fiber

Integrable system

Instability

Quantum electrodynamics

Mathematical physics

Quantum mechanics

Classical mechanics

Nonlinear optics

Physical Review Letters

We report an optical fiber experiment in which we study the nonlinear stage of modulational instability of a plane wave in the presence of a localized perturbation. Using a recirculating fiber loop as the experimental platform, we show that the initial perturbation evolves into an expanding nonlinear oscillatory structure exhibiting some universal characteristics that agree with theoretical predictions based on integrability properties of the focusing nonlinear Schr\"odinger equation. Our experimental results demonstrate the persistence of the universal evolution scenario, even in the presence of small dissipation and noise in an experimental system that is not rigorously of an integrable nature.

Nonlinear Evolution of the Locally Induced Modulational Instability in Fiber Optics