Entanglement fidelity is not a good measurement of entanglement preserving

廖湘萍, 方卯发, 方见树 +1 more

Vahid Azimi Mousolou

Pankaj Kumar, Binayak Kar, Shan-Hsiang Shen

Yang Xiang, Shi‐Jie Xiong

The entanglement fidelity provides a measure of how well the entanglement between two subsystems is preserved in a quantum process. By using a simple model, we show that in some cases this quantity in its original definition fails in the measurement of entanglement preservation. On the contrary, the modified entanglement fidelity, obtained by using a proper local unitary transformation on a subsystem, is shown to exhibit behavior similar to that of the concurrence in quantum evolution.

Yu Jing Guo, Lin Zhang, Huting Yuan

Yang Xiang, Shi‐Jie Xiong

A new formula of entanglement fidelity has been introduced, which can serve as a measure of the preservation of entanglement between two initially entangled subsystems exposed to local noisy environments. For a simple model we derive analytic expressions of concurrence and entanglement fidelity and draw the relationship between them. We find that such entanglement fidelity exhibits the behavior similar to that of the concurrence in quantum evolutions.