Defeating entanglement sudden death by a single local filtering

摘要

Genuine multipartite entanglement of a quantum system can be partially destroyed by local decoherence. Isnit possible to retrieve the entanglement to some extent by a single local operation? The answer to this questionndepends very much on the type of initial genuine entanglement. For initially pure W and cluster states and ifnthe decoherence is given by generalized amplitude damping, the answer is shown to be positive. In this case, thenentanglement retrieving is achieved just by redistributing the remained entanglement of the system.