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Chinese Physics B

Concurrence, tangle and fully entangled fraction

Ming Li, Shao-Ming Fei, Xianqing Li‐Jost

Published Sep 1, 2010• 4 citations
Publisher

Abstract

We show that although we cannot distil a singlet from many pairs of bound entangled states, the concurrence and the tangle of two entangled quantum states are always strictly larger than those of one of them, 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.

DOI
10.1088/1674-1056/19/9/090315

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We show that although we cannot distil a singlet from many pairs of bound entangled states, the concurrence and the tangle of two entangled quantum states are always strictly larger than those of one of them, 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.
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