Description of the thesis topic

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.

This PhD proposal is a fundamental research 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. During the project, 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.

Work Context

The Institut de Physique de Nice (INPHYNI) is attached to the Université Côte d'Azur (UniCA) and the Centre National de la Recherche Scientifique (CNRS). INPHYNI's activities focus on three main areas: Waves and quantum physics; Photonics; and Nonlinear physics, complex fluids and biophysics. The projects developed around these themes range from fundamental physics to applications, and mobilize both theoretical and experimental approaches. These projects benefit from the support of technology platforms, and efficient administrative and technical common services.

The Waves in Complex Media group (https://inphyni.univ-cotedazur.eu/sites/wacs) focuses on controlling the transport properties of classical waves in systems ranging from homogeneous media with complex geometries to periodically or disorderedly structured materials. Thanks to versatile experimental platforms in optics and microwaves, and strong expertise in theory and numerical simulations, the group studies a wide range of topics: mixed dynamics in multimode optical fibers, electromagnetic chaotic reverberation chambers, superfluidity and condensation of light, analog approaches to topological effects in condensed matter, wave scattering or localization. While the studies undertaken are motivated by the desire to answer fundamental questions, they also give rise to numerous application developments.

The researcher recruited will work in collaboration with two CNRS junior researchers. He/she will also benefit from numerous interactions with the other members of the team: 7 researchers, assistant professors or professors, and 4 PhD students.

The position is located in a sector under the protection of scientific and technical potential (PPST), and therefore requires, in accordance with the regulations, that your arrival is authorized by the competent authority of the MESR.