Quantum Information and Computation

Generalized concurrences do not provide necessary and sufficient conditions for entanglement detection

L. Cattaneo, Domenico D’Alessandro

Published Jan 1, 2009• 0 citations

Abstract

We study generalized concurrences as a tool to detect the entanglement of bipartite quantum systems. By considering the case of 2x4 states of rank 2, we prove that generalized concurrences do not, in general, give a necessary and sufficient condition of separability. We identify a set of entangled states which are undetected by this method.

DOI: 10.26421/qic9.1-2-9

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