Expérimental et théorique
In this project we propose to study photon thermalization towards Bose-Einstein condensation in a solution of fluorescent emitters embedded in a strongly scattering medium. Photon thermalization and condensation has been observed for fluorophores inside an optical cavity. Here diffusion replace the cavity and ensures that photons undergo an adequate number of absorption and emission cycles to thermalize with the fluorophores solution. The study will be performed theoretically, numerically and experimentally. We will explore different regimes in which the light emitted by the fluorophores/scattering medium ensemble shows either a fluorescent spectrum or a thermalized spectrum or Bose-Einstein condensation. This will be achieved by changing the density of emitters and the properties of the scattering medium. Different kind of fluorophores and scatterers will also be considered in order to efficiently reach the thermalization regime. This paves the way to new affordable light sources based on easy-to-fabricate scattering materials.