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arXiv · 0908.0886

Entanglement Equivalence of $N$-qubit Symmetric States

P. Mathonet·S. Krins·M. Godefroid·L. Lamata·E. Solano·T. Bastin
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Abstract

We study the interconversion of multipartite symmetric $N$-qubit states under stochastic local operations and classical communication (SLOCC). We demonstrate that if two symmetric states can be connected with a nonsymmetric invertible local operation (ILO), then they belong necessarily to the separable, W, or GHZ entanglement class, establishing a practical method of discriminating subsets of entanglement classes. Furthermore, we prove that there always exists a symmetric ILO connecting any pair of symmetric $N$-qubit states equivalent under SLOCC, simplifying the requirements for experimental implementations of local interconversion of those states.

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P. Mathonet, S. Krins, M. Godefroid, L. Lamata, E. Solano, T. Bastin. 2009-08-17. Entanglement Equivalence of $N$-qubit Symmetric States. https://doi.org/10.1103/physreva.81.052315

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