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MiS Preprint
57/2011
Lower Bound of Concurrence Based on Positive Maps
Xiao-Sheng Li, Xiu-Hong Gao and Shao-Ming Fei
Abstract
We study the concurrence of arbitrary dimensional bipartite quantum systems. An explicit analytical lower bound of concurrence is obtained, which detects entanglement for some quantum states better than some well-known separability criteria, and improves the lower bounds such as from the PPT, realignment criteria and the Breuer's entanglement witness.
