ANR RICOTTA (2025-2029)
  • Reciprocity In COherent lighT Transport phenomenA
  • Multimode optical fibers are the subject of very active research in view of the technological advances expected in the fields of telecommunications and imaging. However, mode dispersion and coupling pose practical implementation problems. RICOTTA is a fundamental project inspired by this issue, which aims to study light scattering in multimode optical fibers with controlled disorder. Scatterers will be photo-inscribed into the fibers using a local direct laser writing device, and the coherent wave transport properties will be measured through the disordered fiber transmission matrix. From the mesoscopic transport literature, it is known that the conductivity of these disordered quasi-1D wires is affected by weak localization, a reciprocity-induced phenomenon. In RICOTTA, we plan to break reciprocity by placing the samples in a magnetic field to induce Faraday effect. This will provide new insights into the transport properties, in addition to the results obtained by measuring other properties such as sample length, number of modes, or disorder intensity. The samples will be characterized by measuring the complete transmission matrix, paving the way for coherent wave control in such systems.
  • https://anr.fr/Project-ANR-24-CE30-7918
ANR STLight (2021-2025)
  • Superfluid and turbulent light in complex media
  • The STLight project focuses on the experimental study of photonic fluids in disordered environments. Superfluidity, the ability of a fluid to move without friction along a pipe or past an obstacle, is one of the most spectacular features of quantum fluids. In nonlinear optics, it manifests as light propagating without being altered by an inhomogeneous environment. The exact opposite happens in the linear case, where light undergoes spatial localisation in disordered media. The main ambition of the STLight project is to study the transition from spatial localisation to superfluidity in complex, but fully controlled, environments, positioning the project at the edge between quantum hydrodynamics and waves in nonlinear complex media. Strong turbulence in complex media will naturally arise in the system and will be investigated. It will, besides addressing transport in disordered optical systems, significantly benefit in both the nonlinear optics and quantum hydrodynamics communities.
  • https://anr.fr/Project-ANR-21-CE30-0008
ANR LOLITOP (2020-2025)
  • Localization of light in disordered topological metamaterials
  • The main objective of the LOLITOP project is to study the interplay between topological physics and disorder-induced effects for light in two-dimensional (2D) metamaterials made of subwavelength resonators. On the one hand, disorder may induce a topologically nontrivial phase – the so-called topological Anderson insulator (TAI). On the other hand, the properties of disorder-induced spatially localized states with energies inside band gaps may depend on the topological indices of adjacent energy bands. The main innovation of the LOLITOP project with respect to the state of the art is the full consideration given to the aspects specific to photonics (polarization of light, resonant nature of scattering, possibility of strong deformations of a lattice) in the study of the impact of disorder on light propagation in topologically nontrivial metamaterials. The main scientific barriers to overcome are due to the needs of adapting the methodology existing to deal with electronic systems to vector electromagnetic waves, and of coping with the fundamental differences between photons and electrons: the absence of charge and the “volatility” of photons that can easily leave the material or be absorbed by it. Fortunately, these difficulties also open a number of new opportunities arising from the possibility of manipulating the polarization of electromagnetic waves (TM or TE) and controlling the number of modes allowed to propagate inside the metamaterial.
  • https://anr.fr/Project-ANR-20-CE30-0003