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Optimal parameter estimation of depolarizing channel

Masahide Sasaki·Masashi Ban·Stephen M. Barnett
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Abstract

We investigate strategies for estimating a depolarizing channel for a finite dimensional system. Our analysis addresses the double optimization problem of selecting the best input probe state and the measurement strategy that minimizes the Bayes cost of a quadratic function. In the qubit case, we derive the Bayes optimal strategy for any finite number of input probe particles when bipartite entanglement can be formed in the probe particles.

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Masahide Sasaki, Masashi Ban, Stephen M. Barnett. 2002-03-22. Optimal parameter estimation of depolarizing channel. https://doi.org/10.1103/physreva.66.022308

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