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

中文翻译：

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具有红外超表面的非线性干涉仪

由亚衍射光散射体或超颖表面组成的光学元件有望减少占位面积并展现光学设备的新功能。特别关注的是用于操纵光束的相位和振幅的超颖表面。可以使用干涉术来进行超表面的表征，但是，这可能很麻烦，特别是在红外（IR）范围内。在这里，我们实现了一种使用可访问的可见光组件来表征在电信IR范围内工作的超颖表面的新方法。将相关的IR和可见光子发射到非线性干涉仪中，以便由超表面施加在IR光子上的相位分布会修改可见光子波长处的干涉。此外，我们表明，该概念可用于使用单个IR超颖表面对可见光束的强度分布进行宽带操纵。我们的方法展现了用于高级光学元件表征的量子干涉测量技术的潜力。