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Optimal cloning of coherent states with a linear amplifier and beam splitters

Samuel L. Braunstein·Nicolas J. Cerf·Sofyan Iblisdir·Peter van Loock·Serge Massar
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Abstract

A transformation achieving the optimal symmetric N-to-M cloning of coherent states is presented. Its implementation only requires a phase-insensitive linear amplifier and a network of beam splitters. An experimental demonstration of this continuous-variable cloner should therefore be in the scope of current technology. The link between optimal quantum cloning and optimal amplification of quantum states is also pointed out.

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Samuel L. Braunstein, Nicolas J. Cerf, Sofyan Iblisdir, Peter van Loock, Serge Massar. 2000-12-11. Optimal cloning of coherent states with a linear amplifier and beam splitters. https://doi.org/10.1103/physrevlett.86.4938

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