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Optical realization of universal quantum cloning

Yun-Feng Huang·Wan-Li Li·Chuan-Feng Li·Yong-Sheng Zhang·Yun-Kun Jiang·Guang-Can Guo
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Abstract

Beyond the no-cloning theorem, the universal symmetric quantum cloning machine was first addressed by Buzek and Hillery. Here, we realized the one-to-two qubits Buzek-Hillery cloning machine with linear optical devices. This method relies on the representation of several qubits by a single photon. We showed that, the fidelities between the two output qubits and the original qubit are both 5/6 (which proved to be the optimal fidelity of one-to-two qubits universal cloner) for arbitrary input pure states.

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Yun-Feng Huang, Wan-Li Li, Chuan-Feng Li, Yong-Sheng Zhang, Yun-Kun Jiang, Guang-Can Guo. 2001-07-10. Optical realization of universal quantum cloning. https://doi.org/10.1103/physreva.64.012315

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