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MiS Preprint
36/2010
Concurrence, Tangle and Fully Entangled Fraction of Quantum Entanglement
Ming Li, Shao-Ming Fei and Xianqing Li-Jost
Abstract
We show that although we can not distill a singlet from many pairs of bound entangled states, the concurrence and tangle of two entangled quantum states are always strictly larger than that of one, even both entangled quantum states are bound entangled. We present a relation between the concurrence and the fidelity of optimal teleportation. We also give new upper and lower bounds for concurrence and tangle.