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Estimating the spectrum of a density matrix with LOCC

Manuel A. Ballester
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Abstract

The problem of estimating the spectrum of a density matrix is considered. Other problems, such as bipartite pure state entanglement, can be reduced to spectrum estimation. A local operations and classical communication (LOCC) measurement strategy is shown which is asymptotically optimal. This means that, for a very large number of copies, it becomes unnecessary to perform collective measurements which should be more difficult to implement in practice.

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Manuel A. Ballester. 2006-02-01. Estimating the spectrum of a density matrix with LOCC. https://doi.org/10.1088/0305-4470/39/7/009

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