An Interferometer Approach For Quantifying Space Varying Polarization From Single Shot Measurement.

We propose a novel single shot experimental strategy to measure the space varying polarization. One such area where we can observe the space varying polarization with small ellipticity is in the astrophysical domain. This approach is based on quantifying the space varying Pancharatnam-Berry (PB) geometrical phase that arises due to the passage of space varying polarized light through a homogeneous anisotropic medium. We first show that the space varying polarization while passing through homogeneous anisotropic medium manifests as the spin (circular polarization) dependent splitting of beam similar to the spin Hall effect of light. Then we move on to quantify this space varying geometrical phase using Mach-Zehnder interferometer which in turn is used to extract the space varying elliptical polarization state of light. Usually to map the spatially varying polarized light stokes vector measurement is used for which it is required to have multiple measurements and takes a relatively long time. In contrast, the proposed method quantifies space varying polarization by measuring space varying PB geometrical phase using a single shot interferometric measurement. This should prove valuable for a number of approaches including solar magnetic field measurement.