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DOE OSTI · 21550024

Optimal phase estimation with arbitrary a priori knowledge

Demkowicz-Dobrzanski, Rafal
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Abstract

The optimal-phase estimation strategy is derived when partial a priori knowledge on the estimated phase is available. The solution is found with the help of the most famous result from the entanglement theory: the positive partial transpose criterion. The structure of the optimal measurements, estimators, and the optimal probe states is analyzed. This Rapid Communication provides a unified framework bridging the gap in the literature on the subject which until now dealt almost exclusively with two extreme cases: almost perfect knowledge (local approach based on Fisher information) and no a priori knowledge (global approach based on covariant measurements). Special attention is paid to a natural a priori probability distribution arising from a diffusion process.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS74 ATOMIC AND MOLECULAR PHYSICSCOMMUNICATIONSDIFFUSIONDISTRIBUTIONINFORMATIONMATHEMATICAL SOLUTIONSPROBABILITYPROBESQUANTUM ENTANGLEMENTQUANTUM INFORMATION

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Demkowicz-Dobrzanski, Rafal. 2011-06-15. Optimal phase estimation with arbitrary a priori knowledge. https://doi.org/10.1103/physreva.83.061802

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