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arXiv · 0803.2747

Irreducible multi-particle correlations in states without maximal rank

D. L. Zhou
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Abstract

In a system of $n$ quantum particles, the correlations are classified into a series of irreducible $k$-particle correlations ($2\le k\le n$), where the irreducible $k$-particle correlation is the correlation appearing in the states of $k$ particles but not existing in the states of $k-1$ particles. A measure of the degree of irreducible $k$-particle correlation is defined based on the maximal entropy construction. By adopting a continuity approach, we overcome the difficulties in calculating the degrees of irreducible multi-particle correlations for the multi-particle states without maximal rank. In particular, we obtain the degrees of irreducible multi-particle correlations in the $n$-qubit stabilizer states and the $n$-qubit generalized GHZ states, which reveals the distribution of multi-particle correlations in these states.

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D. L. Zhou. 2008-04-09. Irreducible multi-particle correlations in states without maximal rank. https://doi.org/10.1103/physrevlett.101.180505

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