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arXiv · 1002.3075

Precision quantum metrology and nonclassicality in linear and nonlinear detection schemes

Ángel Rivas·Alfredo Luis
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Abstract

We examine whether metrological resolution beyond coherent states is a nonclassical effect. We show that this is true for linear detection schemes but false for nonlinear schemes, and propose a very simple experimental setup to test it. We find a nonclassicality criterion derived from quantum Fisher information.

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Ángel Rivas, Alfredo Luis. 2010-07-01. Precision quantum metrology and nonclassicality in linear and nonlinear detection schemes. https://doi.org/10.1103/physrevlett.105.010403

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