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arXiv · 1603.02375

Physical Resources for Quantum-enhanced Phase Estimation

Jaspreet Sahota·Nicolás Quesada·Daniel F. V. James
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Abstract

We study the role of quantum entanglement (particle entanglement and mode entanglement) in optical phase estimation by employing the first and second quantization formalisms of quantum mechanics. The quantum Fisher information (QFI) is expressed as a function of the first and second order optical coherence functions. The resulting form of the QFI elucidates the deriving metrological resources for quantum phase estimation: field intensity and photon detection correlations. In addition, our analysis confirms that mode entanglement is not required for quantum-enhanced interferometry, whereas particle entanglement is a necessary requirement.

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Jaspreet Sahota, Nicolás Quesada, Daniel F. V. James. 2016-03-08. Physical Resources for Quantum-enhanced Phase Estimation. https://doi.org/10.1103/physreva.94.033817

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