title: Quantum cloning with an optical fiber amplifier.
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.
authors.affiliation: Group of Applied Physics, University of Geneva, 20, rue de l'Ecole-de-Médecine, Switzerland.
authors.forename: Sylvain
authors.initials: S
authors.lastname: Fasel
authors.forename: Nicolas
authors.initials: N
authors.lastname: Gisin
authors.forename: Grégoire
authors.initials: G
authors.lastname: Ribordy
authors.forename: Valerio
authors.initials: V
authors.lastname: Scarani
authors.forename: Hugo
authors.initials: H
authors.lastname: Zbinden