Perfect Cluster States from Imperfect Global Entanglement
Michael C. Garrett, David L. Feder
备注：
16 pages IOP style, 4 EPS figures; major revisions to the strategy for growth of cluster states, 2 new figures, several new references; accepted for publication in NJP
The cluster state, the highly entangled state that is the central resource for one-way quantum computing, can be efficiently generated in a variety of physical implementations via global nearest-neighbor interactions. In practice, a systematic phase error is expected in the entangling process, resulting in imperfect cluster states. We present a stochastic measurement technique to generate large perfect cluster states and other graph states with high probability from imperfect cluster states even when their initial entanglement is weak.
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