Harris Jérémie, Boyd Robert W, Lundeen Jeff S
Max Planck Centre for Extreme and Quantum Photonics, Department of Physics, University of Ottawa, 25 Templeton Street, Ottawa, Ontario K1N 6N5, Canada.
Institute of Optics, University of Rochester, Rochester, New York 14627, USA.
Phys Rev Lett. 2017 Feb 17;118(7):070802. doi: 10.1103/PhysRevLett.118.070802. Epub 2017 Feb 15.
Weak value amplification (WVA) is a technique by which one can magnify the apparent strength of a measurement signal. Some have claimed that WVA can outperform more conventional measurement schemes in parameter estimation. Nonetheless, a significant body of theoretical work has challenged this perspective, suggesting WVA to be fundamentally suboptimal. Optimal measurements may not be practical, however. Two practical considerations that have been conjectured to afford a benefit to WVA over conventional measurement are certain types of noise and detector saturation. Here, we report a theoretical study of the role of saturation and pixel noise in WVA-based measurement, in which we carry out a Bayesian analysis of the Fisher information available using a saturable, pixelated, digitized, and/or noisy detector. We draw two conclusions: first, that saturation alone does not confer an advantage to the WVA approach over conventional measurement, and second, that WVA can outperform conventional measurement when saturation is combined with intrinsic pixel noise and/or digitization.
弱值放大（WVA）是一种能够放大测量信号表观强度的技术。一些人声称，在参数估计方面，WVA比更传统的测量方案表现更优。尽管如此，大量的理论研究对这一观点提出了挑战，表明WVA从根本上来说是次优的。然而，最优测量可能并不实际。据推测，相较于传统测量，有两类实际因素能让WVA受益，即特定类型的噪声和探测器饱和。在此，我们报告一项关于饱和与像素噪声在基于WVA的测量中所起作用的理论研究，其中我们使用可饱和、像素化、数字化和/或有噪声的探测器，对可用的费希尔信息进行贝叶斯分析。我们得出两个结论：其一，仅饱和本身并不会使WVA方法相对于传统测量具有优势；其二，当饱和与固有像素噪声和/或数字化相结合时，WVA能够优于传统测量。
