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arXiv · 1005.5295

Local unitary equivalence and entanglement of multipartite pure states

B. Kraus
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Abstract

The necessary and sufficient conditions for the equivalence of arbitrary n-qubit pure quantum states under Local Unitary (LU) operations derived in [B. Kraus Phys. Rev. Lett. 104, 020504 (2010)] are used to determine the different LU-equivalence classes of up to five-qubit states. Due to this classification new parameters characterizing multipartite entanglement are found and their physical interpretation is given. Moreover, the method is used to derive examples of two n-qubit states (with n>2 arbitrary) which have the properties that all the entropies of any subsystem coincide, however, the states are neither LU-equivalent nor can be mapped into each other by general local operations and classical communication.

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B. Kraus. 2010-05-28. Local unitary equivalence and entanglement of multipartite pure states. https://doi.org/10.1103/physreva.82.032121

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