PhD students' seminar: Elise BAILLY

PhD students' seminar given by Elise Bailly from the Nanophotonics group, on 03 February 2022 at 1.15pm in the Amphithéâtre of the Institut d'Optique in Palaiseau, on the topic: " Modelling and control of photoluminescence emitted by a set of thermalised emitters ".

Abstract: "While the emission of light by a single emitter in vacuum is isotropic and characterized by its spectrum, it is possible de tune the photoluminescence by putting an ensemble of thermalized emitters on top of a metasurface. It consists of a spatial arrangement of dielectric or metalic nanoantennas. It is then possible to control the directivity, the spectrum of the polarization of the emitted light. However, knowing how to compute the emission of light by such a system is necessary to design the metasurface, and it might not be straightforward.

Light emission by fluorophores can be computed from the knowledge of the absorption spectrum, thanks to the local Kirchhoff ‘s law. However, this requires very accurate data for the imaginary part of the permittivity.
We report here a technique to measure the refractive index of fluorophores such as dye molecules. We find that the Brendel-Bormann model enables to fit the emission spectra accurately and we apply it to retrieve and explain experimental data. We want to highlight the fact that this method is appropriate to design metasurfaces."