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arXiv · 2011.06612

Many-body nonlocality as a resource for quantum-enhanced metrology

Artur Niezgoda·Jan Chwedenczuk
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Abstract

We demonstrate that a many-body nonlocality is a resource for ultra-precise metrology. This result is achieved by linking the sensitivity of a quantum sensor with a combination of many-body correlation functions that witness the nonlocality. We illustrate our findings with some prominent examples---a collection of spins forming an Ising chain and a gas of ultra-cold atoms in any two-mode configuration.

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Artur Niezgoda, Jan Chwedenczuk. 2020-11-12. Many-body nonlocality as a resource for quantum-enhanced metrology. https://doi.org/10.1103/physrevlett.126.210506

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