Unpolarized light: Poincaré Sphere Engineering - From natural light via quantum optics to applications

We investigate the polarization properties of unpolarized light, first in the temporal domain realized by $1.55 \mu \mathrm{m}$ ASE light emitted by an erbium-doped fiber amplifier and second in the spatial domain by exploiting the polarization dispersion of a Cornu depolarizer. We find novel Stokes parameter correlations and invariances for temporally unpolarized light and novel states on the Poincaré sphere for spatially unpolarized light. All these results give new fresh insight into the field of classical polarization with interesting promising quantum and sensing application perspectives.