Topographic optical fibers : new prospects in nonlinear guided-wave optics
The proposal concerns the impact of controlled longitudinal variations (periodic or not) of optical fibers guiding properties with the aim of investigating new perspectives in the field of nonlinear photonics. The objective of this project is thus to provide innovative optical fibers with axially-varying dispersive and nonlinear parameters in a controlled way (which we term topographic fibers). The ability to fabricate optical fibers with controlled axial topography really is an actual technological breakthrough, since the new degree of freedom brought by the fiber topography should allow the simultaneous control of linear and nonlinear properties along the fiber. Topographic fibers will thus serve as innovative platforms to motivate new theoretical studies, perform ground-breaking experiments and stimulate new ways of thinking about nonlinear photonics.
1. S. F. Wang et al., “Bouncing of a dispersive wave in a solitonic cage”, Opt. Lett. 40 (14), p. 3320-3323 (2015).
2. A. Bendahmane et al., “Observation of the stepwise blue shift of a dispersive wave preceding its trapping by a soliton”, Opt. Expr
The TOPWAVE project deals with the field of nonlinear guided-wave photonics with links to nonlinear dynamics. The origin of the project lies in the fact that nonlinear fiber optics over the last 40 years has essentially been based on fibers with longitudinal uniformity. Yet the possibility to study nonlinear propagation effects when the guidance properties vary along the same direction as the evolution of the optical field will allow to explore new directions in nonlinear fiber optics and more generally in nonlinear physics. The present proposal thus aims at scanning opportunities brought by this new kind of optical waveguides which we term “topographic fibers”. Most of this project is based on preliminary results which have allowed to identify several propagation regimes (ranging from femtosecond to quasi-continuous-wave time scales) in which the axially controlled fiber topography plays a major role.
More precisely, we will first focus on the spontaneous modulation instability (MI) experienced by a quasi-continuous-wave propagating in an optical waveguide which dispersion evolves longitudinally and periodically. The new degree of freedom brought by the fiber periodicity is expected to entirely revisit the MI dynamics to generate new physical effects. In addition to these deterministic investigations, we also propose to extend these pioneering studies into the field of quantum optics. Indeed, we will focus on drawing a rigorous analogy between spontaneous MI in a fiber with spatially oscillating dispersion and the dynamical Casimir effect in which a time-oscillating mirror is predicted to irradiate photons from vacuum quantum fluctuations. This work will require an accurate characterization of correlations between all photons involved in the spontaneous MI process, which we will further exploit to design and demonstrate improved fiber-integrated sources of entangled photons based on topographic fibers for applications in quantum optics experiments.
Another aspect of the proposal concerns the generation and control of periodic structures in space and time (known as Akhmediev breathers) from stimulated MI, in which MI is driven by a coherent signal instead of growing from quantum noise. These analytical solutions of the nonlinear Schrödinger equation are considered as representative prototypes of infamous hydrodynamic rogue waves observed in the ocean. In optics however, studies have focused on fibers with a dispersion uniformity, while the seabed topography is rarely flat. In this project we propose to take benefit from the extraordinary experimental platform constituted by topographic fibers to investigate the behavior of Akhmediev breathers in the presence of complex topography. We plan to establish closed links between fiber and deep ocean topographies in order to extend our conclusions to hydrodynamical rogue waves.
The last area covered by our proposal deals with the propagation of fundamental solitons in nonlinear fiber optics. Usually, intrapulse stimulated Raman scattering causes them to experience a frequency shift at a rate which is mainly imposed by fiber and pump properties. In this project we plan to go beyond this limitation by adding a new degree of freedom to the system by using topographic fibers. The aim will be to locally tailor linear and nonlinear properties of optical fibers in order to continuously shape a propagating ultrashort pulse and transform it into a high-energy soliton with controlled spectro-temporal properties, while harnessing detrimental propagation effects. This will open up fundamental studies about the robustness of solitons against strong variations of dispersion and nonlinearity due to fiber topography and applications in new optical sources with tailored pulse color and duration.
Finally, let us precise that this project will be performed within the stimulating framework of labeled Equipex Flux and Labex Cempi national projects from which it will thus take full benefit.
Monsieur Alexandre Kudlinski (Laboratoire de Physique des Lasers, Atomes et Molécules) – email@example.com
The author of this summary is the project coordinator, who is responsible for the content of this summary. The ANR declines any responsibility as for its contents.
PhLAM Laboratoire de Physique des Lasers, Atomes et Molécules
Help of the ANR 261,565 euros
Beginning and duration of the scientific project: January 2014 - 42 Months