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arXiv · 2109.03581

Qubit State Discrimination using Post-measurement Information

Donghoon Ha·Jeong San Kim·Younghun Kwon
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Abstract

We consider the optimal discrimination of nonorthogonal qubit states with post-measurement information and provide an analytic structure of the optimal measurements. We also show that there is always a null optimal measurement when post-measurement information is given. Further, in discriminating four states using post-measurement information, we analytically provide the optimal probability of correct guessing and show that the uniqueness of optimal measurement is equivalent to the non-existence of non-null optimal measurement with post-measurement information.

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Donghoon Ha, Jeong San Kim, Younghun Kwon. 2022-01-22. Qubit State Discrimination using Post-measurement Information. https://doi.org/10.1007/s11128-022-03414-y

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