Universal Quantum Cloning Machines for Two Identical Mixed Qubits
YANG Shuai, ZHAO Mei-Sheng, LIU Nai-Le, CHEN Zeng-Bing
Hefei National Laboratory for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China, Hefei 230026
Universal Quantum Cloning Machines for Two Identical Mixed Qubits
YANG Shuai;ZHAO Mei-Sheng;LIU Nai-Le;CHEN Zeng-Bing
Hefei National Laboratory for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China, Hefei 230026
摘要We present a series of universal quantum cloning machines for two identical mixed qubits. Every machine is optimal in the sense that it achieves the optimal bound of the single copy shrinking factor. Unlike in the case of pure state cloning, the single copy shrinking factor does not uniquely determine the cloning map in the case of mixed state cloning.
Abstract：We present a series of universal quantum cloning machines for two identical mixed qubits. Every machine is optimal in the sense that it achieves the optimal bound of the single copy shrinking factor. Unlike in the case of pure state cloning, the single copy shrinking factor does not uniquely determine the cloning map in the case of mixed state cloning.
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2007, Vol. 24 
