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MiS Preprint
67/2007
Local Equivalence of Rank-Two Quantum Mixed States
Sergio Albeverio, Shao-Ming Fei and Debashish Goswami
Abstract
We investigate the equivalence of quantum mixed states under local unitary transformations. For a class of rank-two 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.
