Non-linear interferometry with infrared metasurfaces

Abstract The optical elements comprised of sub-diffractive light scatterers, or metasurfaces, hold a promise to reduce the footprint and unfold new functionalities devices. A particular interest is focused on metasurfaces for manipulation phase amplitude beams. Characterisation can be performed using interferometry, which, however, may cumbersome, specifically in infrared (IR) range. Here, we realise method characterising operating telecom IR range accessible components visible light. Correlated photons are launched into non-linear interferometer so that profile, imposed by metasurface photons, modifies interference at photon wavelength. Furthermore, show this concept used broadband intensity profile beam single metasurface. Our unfolds potential quantum interferometry characterization advanced elements.