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Optimal quantum cloning via spin networks

Qing Chen·Jianhua Cheng·Ke-Lin Wang·Jiangfeng Du
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Abstract

In this paper we present an approach to quantum cloning via free dynamical evolution of spin networks. By properly designing the network and the couplings between spins, we show that optimal 1->M phase covariant cloning can be achieved without any external control. Especially, when M is an odd number, the optimal phase-covariant cloning can be achieved without ancillas. Moreover, we demonstrate that the same framework is capable for optimal 1->2 universal cloning.

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Qing Chen, Jianhua Cheng, Ke-Lin Wang, Jiangfeng Du. 2005-10-19. Optimal quantum cloning via spin networks. https://doi.org/10.1103/physreva.74.034303

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