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arXiv · 1610.08272

Probabilistic metrology or how some measurement outcomes render ultra-precise estimates

J. Calsamiglia·B. Gendra·R. Munoz-Tapia·E. Bagan
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Abstract

We show on theoretical grounds that, even in the presence of noise, probabilistic measurement strategies (which have a certain probability of failure or abstention) can provide, upon a heralded successful outcome, estimates with a precision that exceeds the deterministic bounds for the average precision. This establishes a new ultimate bound on the phase estimation precision of particular measurement outcomes (or sequence of outcomes). For probe systems subject to local dephasing, we quantify such precision limit as a function of the probability of failure that can be tolerated. Our results show that the possibility of abstaining can set back the detrimental effects of noise.

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J. Calsamiglia, B. Gendra, R. Munoz-Tapia, E. Bagan. 2016-10-26. Probabilistic metrology or how some measurement outcomes render ultra-precise estimates. https://doi.org/10.1088/1367-2630/18/10/103049

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