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arXiv 0706.20002007-06quant-ph

General Depolarized Pure States: Identification and Properties

Mark S. Byrd, Gavin K. Brennen

备注：: 1 figure, 9 pages, revtex4, slightly rewritten, reorganized, new section
发表信息：: Physics Letters A, Vol. 372, 1770 (2008)
DOI：: 10.1016/j.physleta.2007.10.074

英文摘要：

The Schmidt decomposition is an important tool in the study of quantum systems especially for the quantification of the entanglement of pure states. However, the Schmidt decomposition is only unique for bipartite pure states, and some multipartite pure states. Here a generalized Schmidt decomposition is given for states which are equivalent to depolarized pure states. Experimental methods for the identification of this class of mixed states are provided and some examples are discussed which show the utility of this description. A particularly interesting example provides, for the first time, an interpretation of the number of negative eigenvalues of the density matrix.

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