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Irreducible multi-particle correlations in states without maximal rank

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 Added by Duanlu Zhou
 Publication date 2008
  fields Physics
and research's language is English
 Authors D.L. Zhou




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In a system of $n$ quantum particles, the correlations are classified into a series of irreducible $k$-particle correlations ($2le kle n$), 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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