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Continuous-Variable Quantum Information Distributor: Reversible Telecloning

Jing Zhang·Changde Xie·Kunchi Peng
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Abstract

We propose a scheme of continuous-variable reversible telecloning, which broadcast the information of an unknown state without loss from a sender to several spatially separated receivers exploiting multipartite entanglement as quantum channels. In this scheme, quantum information of an unknown state is distributed into $M$ optimal clones and $M-1$ anticlones using $2M$% -partite entanglement. For the perfect quantum information distribution that is optimal cloning, $2M$-partite entanglement is required to be a maximum two-party entanglement. Comparing with the quantum telecloning proposed by Loock and Braunstein [Phys. Rev. Lett. 87, 247901 (2001)], this protocol produces the anticlones (or time-reversed state) of the unknown quantum state, thus, keep all information of an unknown state.

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Jing Zhang, Changde Xie, Kunchi Peng. 2005-10-21. Continuous-Variable Quantum Information Distributor: Reversible Telecloning. https://doi.org/10.1103/physreva.73.042315

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