Opt. Express 19, 21313–21320 (2011)

Credit: © 2011 OSA

Shining polarized light into a medium that exhibits complex scattering is well-known to cause depolarization of the incident beam. Jacques Sorrentini, Myriam Zerrad, Gabriel Soriano and Claude Amra from the Institut Fresnel at the Université d'Aix-Marseille in France have now shown that such media can also locally increase the polarization of an incident depolarized beam. The team considered a coherent and depolarized beam illuminating a scattering medium whose properties are defined by the Jones matrix. Instead of using time-consuming exact theories to model the scattering behaviour, the team employed an approach based on obtaining speckle patterns from the Fourier transform of random phasor matrices. The theoretical results are in good agreement with experiments, which used MgF2 as the scattering medium and unpolarized red light (632.8 nm) from a He–Ne laser. Using four Stokes images to measure the scattered light, the researchers showed that the scattering medium caused the incident degree of polarization to increase from 4% to around 75%.