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State estimation from pair of conjugate qudits

Xiang-Fa Zhou·Yong-Sheng Zhang·Guang-Can Guo
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Abstract

We show that, for $N$ parallel input states, an anti-linear map with respect to a specific basis is essentially a classical operator. We also consider the information contained in phase-conjugate pairs $|ϕ> |ϕ^*>$, and prove that there is more information about a quantum state encoded in phase-conjugate pairs than in parallel pairs.

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Xiang-Fa Zhou, Yong-Sheng Zhang, Guang-Can Guo. 2006-09-21. State estimation from pair of conjugate qudits. https://doi.org/10.1103/physreva.74.042324

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