title: Phase Transitions in Diffusion of Light.
abstract: It has been a long time belief that, with increasing the scattering strength of multiple scattering media, the transport of light gradually slows down and, eventually, comes to a halt corresponding to a localized state. Here we present experimental evidence that different stages emerge in this evolution, which cannot be described by classical diffusion with conventional scaling arguments. A microscopic model captures the relevant aspects of electromagnetic wave propagation and explains the competing mechanisms that prevent the three-dimensional wave localization. We demonstrate that strong evanescent-field couplings hinder the localization of wave resonances and, therefore, impede the slowing down of diffusion. The emerging out of equilibrium steady-state process resembles the diffusion of classical particles in spatially correlated random potentials and the thermalization of matter waves due to atomic collisions.
authors.affiliation: CREOL, The College of Optics and Photonics, University of Central Florida, Orlando, Florida 32816, USA.|Department of Physics, University of Central Florida, 4000 Central Florida Boulevard, Orlando, Florida 32816, USA.
authors.forename: Roxana
authors.initials: R
authors.lastname: Rezvani Naraghi
authors.affiliation: CREOL, The College of Optics and Photonics, University of Central Florida, Orlando, Florida 32816, USA.
authors.forename: Aristide
authors.initials: A
authors.lastname: Dogariu