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arXiv · 1601.05866

Invertible condition of quantum Fisher information matrix for a mixed qubit

Ping Yue·Li Ge·Qiang Zheng
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Abstract

Estimating multiparamter simultaneously as precise as possible is an important goal of quantum metrolo- gy. As a first step to this end, here we give a condition determining whether two arbitrary parameters can be estimated simultaneously for a qubit in the mixed state. An application of this condition is shown.

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Ping Yue, Li Ge, Qiang Zheng. 2016-01-22. Invertible condition of quantum Fisher information matrix for a mixed qubit. https://doi.org/10.1140/epjd%2Fe2015-60460-5

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