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Entropy of phase measurement: Quantum phase via quadrature measurement

Zdeněk Hradil·Robert Myška·Tomáš Opatrný·Jiří Bajer
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Abstract

The content of phase information of an arbitrary phase--sensitive measurement is evaluated using the maximum likelihood estimation. The phase distribution is characterized by the relative entropy--a nonlinear functional of input quantum state. As an explicit example the multiple measurement of quadrature operator is interpreted as quantum phase detection achieving the ultimate resolution predicted by the Fisher information.

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Zdeněk Hradil, Robert Myška, Tomáš Opatrný, Jiří Bajer. 1995-06-02. Entropy of phase measurement: Quantum phase via quadrature measurement. https://doi.org/10.1103/physreva.53.3738

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