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Optimal multicopy asymmetric Gaussian cloning of coherent states

Jaromir Fiurasek·Nicolas J. Cerf
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Abstract

We investigate the asymmetric Gaussian cloning of coherent states which produces M copies from N input replicas, such that the fidelity of all copies may be different. We show that the optimal asymmetric Gaussian cloning can be performed with a single phase-insensitive amplifier and an array of beam splitters. We obtain a simple analytical expression characterizing the set of optimal asymmetric Gaussian cloning machines.

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Jaromir Fiurasek, Nicolas J. Cerf. 2006-10-24. Optimal multicopy asymmetric Gaussian cloning of coherent states. https://doi.org/10.1103/physreva.75.052335

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