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Concurrence classes for an arbitrary multi-qubit state based on positive operator valued measure

Hoshang Heydari
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Abstract

In this paper, we propose concurrence classes for an arbitrary multi-qubit state based on orthogonal complement of a positive operator valued measure, or POVM in short, on quantum phase. In particular, we construct concurrence for an arbitrary two-qubit state and concurrence classes for the three- and four-qubit states. And finally, we construct $W^{m}$ and $GHZ^{m}$ class concurrences for multi-qubit states. The unique structure of our POVM enables us to distinguish different concurrence classes for multi-qubit states.

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Hoshang Heydari. 2005-12-03. Concurrence classes for an arbitrary multi-qubit state based on positive operator valued measure. https://doi.org/10.1088/0305-4470/38/50/009

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