Experimental quantum cloning with prior partial information.

@article{Du2005ExperimentalQC,
  title={Experimental quantum cloning with prior partial information.},
  author={Jiangfeng Du and Thomas Durt and Ping Zou and Hui Li and Leong Chuan Kwek and C. H. Lai and C. H. Oh and Artur K. Ekert},
  journal={Physical review letters},
  year={2005},
  volume={94 4},
  pages={
          040505
        }
}
When prior partial information about a state to be cloned is available, it can be cloned with a fidelity higher than that of universal quantum cloning. We experimentally verify this intriguing relationship between the cloning fidelity and the prior information by reporting the first experimental optimal quantum state-dependent cloner, using nuclear magnetic resonance techniques. Our experiments may further cast important implications into many quantum information processing protocols. 

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