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Universal Algorithm for Optimal Estimation of Quantum States from Finite Ensembles

Radoslav Derka·Vladimir Buzek·Artur Ekert
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Abstract

We present a universal algorithm for the optimal quantum state estimation of an arbitrary finite dimensional system. The algorithm specifies a physically realizable positive operator valued measurement (POVM) on a finite number of identically prepared systems. We illustrate the general formalism by applying it to different scenarios of the state estimation of N independent and identically prepared two-level systems (qubits).

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Radoslav Derka, Vladimir Buzek, Artur Ekert. 1997-07-16. Universal Algorithm for Optimal Estimation of Quantum States from Finite Ensembles. https://doi.org/10.1103/physrevlett.80.1571

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