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arXiv · 0910.5622

Mechanism of entanglement preservation

Qing-Jun Tong·Jun-Hong An·Hong-Gang Luo·C. H. Oh
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Abstract

We study the entanglement preservation of two qubits locally interacting with their reservoirs. We show that the existence of a bound state of the qubit and its reservoir and the non-Markovian effect are two essential ingredients and their interplay plays a crucial role in preserving the entanglement in the steady state. When the non-Markovian effect is neglected, the entanglement sudden death (ESD) is reproduced. On the other hand, when the non-Markovian is significantly strong but the bound state is absent, the phenomenon of the ESD and its revival is recovered. Our formulation presents a unified picture about the entanglement preservation and provides a clear clue on how to preserve the entanglement in quantum information processing.

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Qing-Jun Tong, Jun-Hong An, Hong-Gang Luo, C. H. Oh. 2010-05-24. Mechanism of entanglement preservation. https://doi.org/10.1103/physreva.81.052330

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