Optimal Monitoring of Small Polarization Perturbations with Metasurfaces

We reveal that dielectric metasurfaces can perform tailored non-conservative transformations optimized for monitoring of small deviations around arbitrarily chosen linear, circular, or elliptical polarizations. We demonstrate that such metasurfaces can convert the anchor polarization to horizontal linear polarization with attenuated power, while they map the small deviations to vertical linear polarization with nearly full power, delivering amplified vertical-to-horizontal polarization ratios for sensitive and convenient single-shot detection.