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Optimal estimation of multiple phases

Chiara Macchiavello
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Abstract

We study the issue of simultaneous estimation of several phase shifts induced by commuting operators on a quantum state. We derive the optimal positive operator-valued measure corresponding to the multiple-phase estimation. In particular, we discuss the explicit case of the optimal detection of double phase for a system of identical qutrits and generalise these results to optimal multiple phase detection for d-dimensional quantum states.

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Chiara Macchiavello. 2003-04-18. Optimal estimation of multiple phases. https://doi.org/10.1103/physreva.67.062302

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