The quantum nature of optical near-fields is interesting from a theoretical perspective and of importance for practical applications, such as high-resolution imaging, sensing and antenna-coupled quantum light sources. In this work we use a custom-designed superconducting nanowire single-photon detector (SNSPD) to directly read out the near-field interaction between source and detector. We use a subwavelength-sized aperture at the end of an optical fiber to record spatial near-field maps and to measure the distance dependence of the optical near-field interaction. Our measurements can be well described by a superposition of evanescent source fields with no noticeable probe-sample coupling. Our approach can be used for further studies of quantum near-field interactions and for the development of near-field imaging techniques with single quantum sensitivity.

中文翻译：

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使用超导纳米线探测器进行光学近场映射

从理论的角度来看，光学近场的量子性质很有趣，对实际应用也很重要，例如高分辨率成像、传感和天线耦合量子光源。在这项工作中，我们使用定制设计的超导纳米线单光子探测器 (SNSPD) 直接读出源和探测器之间的近场相互作用。我们在光纤末端使用亚波长大小的孔径来记录空间近场图并测量光学近场相互作用的距离依赖性。我们的测量可以通过渐逝源场的叠加来很好地描述，没有明显的探针 - 样品耦合。