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Optimal partial estimation of quantum states from several copies

Ladislav Mista Jr.·Jaromir Fiurasek
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Abstract

We derive analytical formula for the optimal trade-off between the mean estimation fidelity and the mean fidelity of the qubit state after a partial measurement on N identically prepared qubits. We also conjecture analytical expression for the optimal fidelity trade-off in case of a partial measurement on N identical copies of a d-level system.

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Ladislav Mista Jr., Jaromir Fiurasek. 2006-06-13. Optimal partial estimation of quantum states from several copies. https://doi.org/10.1103/physreva.74.022316

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