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Experimental demonstration of an efficient quantum phase-covariant cloning and its possible applications to simulating eavesdropping in quantum cryptography

Jiangfeng Du·Thomas Durt·Ping Zou·L. C. Kwek·C. H. Lai·C. H. Oh·Artur Ekert
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Abstract

We describe a nuclear magnetic resonance (NMR) experiment which implements an efficient one-to-two qubit phase-covariant cloning machine(QPCCM). In the experiment we have achieved remarkably high fidelities of cloning, 0.848 and 0.844 respectively for the original and the blank qubit. This experimental value is close to the optimal theoretical value of 0.854. We have also demonstrated how to use our phase-covariant cloning machine for quantum simulations of bit by bit eavesdropping in the four-state quantum key distribution protocol.

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Jiangfeng Du, Thomas Durt, Ping Zou, L. C. Kwek, C. H. Lai, C. H. Oh, Artur Ekert. 2003-11-04. Experimental demonstration of an efficient quantum phase-covariant cloning and its possible applications to simulating eavesdropping in quantum cryptography. https://arxiv.org/abs/quant-ph/0311010

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