2014/03/31 by Alexander Holm Kiilerich, Klaus Mølmer · 3 citations
Physics and Astronomy · #quant-ph
published as Phys. Rev. A. 89, 052110 (2014) · 9 pages, 7 figures
arxiv created 2014/05/12 · arxiv updated 2014/05/13
Detection of radiation signals is at the heart of precision metrology and sensing. In this article we show how the fluctuations in photon counting signals can be exploited to optimally extract information about the physical parameters that govern the dynamics of the emitter. For a simple two-level emitter subject to photon counting, we show that the Fisher information and the Cramér- Rao sensitivity bound based on the full detection record can be evaluated from the waiting time distribution in the fluorescence signal which can, in turn, be calculated for both perfect and imperfect detectors by a quantum trajectory analysis. We provide an optimal estimator achieving that bound.