Extraction of information about the multidimensional optical properties of free-space and guided optical beams is critical in modern photonics. To date, planar, most beam-information detection systems destroy or substantially modify the original wave fronts of an incident beam in the detection process. Here, we demonstrate an all-silica beam information detection system that effectively taps into a free space optical beam while leaving the original wavefronts virtually unaffected. This is accomplished by diverting a small (few percent) fraction of the light through the interaction with a silica metasurface based on the Pancharatnam-Berry phase. A chiroptical spectrometer and a multichannel angular momentum detector are proposed to demonstrate the multifunctionality of this design principle. The concept and device proposed here may pave the way to in situ beam monitoring and may provide a novel method to collect optical information for emerging augmented reality technologies.

中文翻译：

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全硅超表面的自由空间光束攻丝

关于自由空间和引导光束的多维光学特性的信息的提取在现代光子学中至关重要。迄今为止，平面的大多数光束信息检测系统在检测过程中会破坏或实质上改变入射光束的原始波阵面。在这里，我们演示了一种全硅胶束信息检测系统，该系统可以有效地进入自由空间光束，而实际上不影响原始波阵面。这是通过与基于Pancharatnam-Berry相的二氧化硅超表面相互作用而转移一小部分（百分之几）的光来实现的。为了证明该设计原理的多功能性，提出了一种脊波谱仪和多通道角动量检测器。