Maslova Valeria, Ermolaev Georgy, Andrianov Evgeny S, Arsenin Aleksey V, Volkov Valentyn S, Baranov Denis G
Moscow Center for Advanced Studies, Moscow, 123592, Russia.
Emerging Technologies Research Center, XPANCEO, Internet City, Emmay Tower, Dubai, United Arab Emirates.
Nanophotonics. 2025 Jun 19;14(14):2463-2472. doi: 10.1515/nanoph-2025-0101. eCollection 2025 Jul.
Topological singularities of optical response functions - such as reflection amplitudes - enable elegant practical applications ranging from analog signal processing to novel molecular sensing approaches. A phase singularity-based refractometric sensor monitors the rapidly evolving of the optical field near the point of phase singularity, in contrast to the reflection zero in traditional surface plasmon polariton sensors. This raises a natural question: What happens with the sensitivity and resolution of such a sensor when it operates close to a zero of the response function, where the detected signal may be greatly influenced by various noise sources? In this paper, we systematically study the effect of the shot noise on the performance of a generic phase singularity-based refractometric sensor. We develop a theoretical model of a spectroscopic ellipsometry-based system operating near a phase singularity and couple the macroscopic optical picture of the detection with a quantum shot noise model. Within the developed model, we illustrate how the shot noise of the detector comes into play and study its effect on the sensitivity and resolution of the refractometric sensor. Our results suggest that such an ellipsometry-based phase singularity sensor remains stable even in the presence of shot noise near the point of zero reflection.
光学响应函数的拓扑奇点——如反射振幅——使得从模拟信号处理到新型分子传感方法等诸多优雅的实际应用成为可能。与传统表面等离激元极化子传感器中的反射零点不同，基于相位奇点的折射传感器监测相位奇点附近光场的快速变化。这就引出了一个自然的问题：当这种传感器在接近响应函数零点的位置工作时，其灵敏度和分辨率会发生什么变化？在该位置，检测到的信号可能会受到各种噪声源的极大影响。在本文中，我们系统地研究了散粒噪声对基于通用相位奇点的折射传感器性能的影响。我们建立了一个基于光谱椭偏仪的系统在相位奇点附近工作的理论模型，并将检测的宏观光学图像与量子散粒噪声模型相结合。在建立的模型中，我们说明了探测器的散粒噪声是如何起作用的，并研究了其对折射传感器灵敏度和分辨率的影响。我们的结果表明，即使在接近零反射点存在散粒噪声的情况下，这种基于椭偏仪的相位奇点传感器仍保持稳定。
