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arXiv · 1901.07482

Squeezing metrology: a unified framework

Lorenzo Maccone·Alberto Riccardi
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Abstract

Quantum metrology theory has up to now focused on the resolution gains obtainable thanks to the entanglement among N probes. Typically, a quadratic gain in resolution is achievable, going from the 1/sqrt(N) of the central limit theorem to the 1/N of the Heisenberg bound. Here we focus instead on quantum squeezing and provide a unified framework for metrology with squeezing, showing that, similarly, one can generally attain a quadratic gain when comparing the resolution achievable by a squeezed probe to the best N-probe classical strategy achievable with the same energy. Namely, here we give a quantification of the Heisenberg squeezing bound for arbitrary estimation strategies that employ squeezing. Our theory recovers known results (e.g.~in quantum optics and spin squeezing), but it uses the general theory of squeezing and holds for arbitrary quantum systems.

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Lorenzo Maccone, Alberto Riccardi. 2019-01-22. Squeezing metrology: a unified framework. https://doi.org/10.22331/q-2020-07-09-292

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