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arXiv · 1304.7609

Quantum metrology: why entanglement?

Lorenzo Maccone
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Abstract

We show why and when entanglement is needed for quantum-enhanced precision measurements, and which type of entanglement is useful. We give a simple, intuitive construction that shows how entanglement transforms parallel estimation strategies into sequential ones of same precision. We employ this argument to generalize conventional quantum metrology, to identify a class of noise whose effects can be easily managed, and to treat the case of indistinguishable probes (such as interferometry with light).

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Lorenzo Maccone. 2013-04-29. Quantum metrology: why entanglement?. https://doi.org/10.1103/physreva.88.042109

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