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Optimal discrimination of mixed quantum states involving inconclusive results

Jaromir Fiurasek·Miroslav Jezek
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Abstract

We propose a generalized discrimination scheme for mixed quantum states. In the present scenario we allow for certain fixed fraction of inconclusive results and we maximize the success rate of the quantum-state discrimination. This protocol interpolates between the Ivanovic-Dieks-Peres scheme and the Helstrom one. We formulate the extremal equations for the optimal positive operator valued measure describing the discrimination device and establish a criterion for its optimality. We also devise a numerical method for efficient solving of these extremal equations.

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Jaromir Fiurasek, Miroslav Jezek. 2002-08-20. Optimal discrimination of mixed quantum states involving inconclusive results. https://doi.org/10.1103/physreva.67.012321

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