Journal of the European Optical Society - Rapid publications, Vol 9 (2014)

Quantum conditional cloning of continuous variable entangled states

K. Liu, J. R. Gao


We extend the technique of conditional preparation to a quantum cloning machine, and present a protocol of 1 -> 2 conditional cloning of squeezed state and entanglement states. It is shown that the entanglement degree of the cloned entangled states can be well preserved even when the fidelity between the input and output states is beyond the limit of 4/9. This scheme is practicable since only the linear elements of beam splitters, homodyne detections, optical modulations and electrical trigger system, are involved.

© The Authors. All rights reserved. [DOI: 10.2971/jeos.2014.14057]

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