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On the general problem of quantum phase estimation

G. M. D'Ariano·C. Macchiavello·M. F. Sacchi
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Abstract

The problem of estimating a generic phase-shift experienced by a quantum state is addressed for a generally degenerate phase shift operator. The optimal positive operator-valued measure is derived along with the optimal input state. Two relevant examples are analyzed: i) a multi-mode phase shift operator for multipath interferometry; ii) the two mode heterodyne phase detection.

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G. M. D'Ariano, C. Macchiavello, M. F. Sacchi. 1998-12-15. On the general problem of quantum phase estimation. https://doi.org/10.1016/s0375-9601(98)00702-6

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