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arXiv · 0704.1375

Decrease of entanglement by local operations in the Dür-Cirac method

Yukihiro Ota·Motoyuki Yoshida·Ichiro Ohba
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Abstract

One cannot always obtain information about entanglement by the Dür-Cirac (DC) method. The impracticality is attributed to the decrease of entanglement by local operations in the DC method. We show that, even in 2--qubit systems, there exist states whose entangled property the DC method never evaluates. The class of such states in 2--qubit systems is completely characterized by the value of the fully entangled fraction. Actually, a state whose fully entangled fraction is less than or equal to 1/2 is always transformed into a separable state by local operations in the DC method, even if it has negative partial transposition.

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Yukihiro Ota, Motoyuki Yoshida, Ichiro Ohba. 2007-04-11. Decrease of entanglement by local operations in the Dür-Cirac method. https://arxiv.org/abs/0704.1375

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