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arXiv:0711.1210 · Journal of Physics A Mathematical and Theoretical

Local equivalence of rank-2 quantum mixed states

Sergio A Albeverio, Shao-Ming Fei, Debashish Goswami

Published Aug 21, 2007• 7 citations
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Abstract

We investigate the equivalence of quantum mixed states under local unitary transformations. For a class of rank-2 mixed states, a sufficient and necessary condition of local equivalence is obtained by giving a complete set of invariants under local unitary transformations, such that two states in this class are locally equivalent if and only if all these invariants have equal values for them.

DOI
10.1088/1751-8113/40/36/011

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