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arXiv · 2102.03223

Quantum metrology and coherence

Laura Ares·Alfredo Luis
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Abstract

We address the relation between quantum metrological resolution and coherence. We examine this dependence in two manners: we develop a quantum Wiener-Kintchine theorem for a suitable model of quantum ruler, and we compute the Fisher information. The two methods have the virtue of including both the contributions of probe and measurement on an equal footing. We illustrate this approach with several examples of linear and nonlinear metrology. Finally, we optimize resolution regarding coherence as a finite resource.

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Laura Ares, Alfredo Luis. 2021-02-08. Quantum metrology and coherence. https://doi.org/10.1364/ol.439197

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