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Sensitivity optimization in quantum parameter estimation

F. Verstraete·A. C. Doherty·H. Mabuchi
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Abstract

We present a general framework for sensitivity optimization in quantum parameter estimation schemes based on continuous (indirect) observation of a dynamical system. As an illustrative example, we analyze the canonical scenario of monitoring the position of a free mass or harmonic oscillator to detect weak classical forces. We show that our framework allows the consideration of sensitivity scheduling as well as estimation strategies for non-stationary signals, leading us to propose corresponding generalizations of the Standard Quantum Limit for force detection.

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F. Verstraete, A. C. Doherty, H. Mabuchi. 2001-04-24. Sensitivity optimization in quantum parameter estimation. https://doi.org/10.1103/physreva.64.032111

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