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Optimal generalized quantum measurements for arbitrary spin systems

A. Acin·J. I. Latorre·P. Pascual
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Abstract

Positive operator valued measurements on a finite number of N identically prepared systems of arbitrary spin J are discussed. Pure states are characterized in terms of Bloch-like vectors restricted by a SU(2 J+1) covariant constraint. This representation allows for a simple description of the equations to be fulfilled by optimal measurements. We explicitly find the minimal POVM for the N=2 case, a rigorous bound for N=3 and set up the analysis for arbitrary N.

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A. Acin, J. I. Latorre, P. Pascual. 1999-04-14. Optimal generalized quantum measurements for arbitrary spin systems. https://doi.org/10.1103/physreva.61.022113

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