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Quantum cloning with an optical fiber amplifier

Sylvain Fasel·Nicolas Gisin·Gregoire Ribordy·Valerio Scarani·Hugo Zbinden
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Abstract

It has been shown theoretically that a light amplifier working on the physical principle of stimulated emission should achieve optimal quantum cloning of the polarization state of light. We demonstrate close-to-optimal universal quantum cloning of polarization in a standard fiber amplifier for telecom wavelengths. For cloning 1 --> 2 we find a fidelity of 0.82, the optimal value being 5/6 = 0.83.

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Sylvain Fasel, Nicolas Gisin, Gregoire Ribordy, Valerio Scarani, Hugo Zbinden. 2002-08-26. Quantum cloning with an optical fiber amplifier. https://doi.org/10.1103/physrevlett.89.107901

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