title: Quantum cloning for absolute radiometry.
abstract: In the quantum regime information can be copied with only a finite fidelity. This fidelity gradually increases to 1 as the system becomes classical. In this Letter we show how this fact can be used to directly measure the amount of radiated power. We demonstrate how these principles can be used to build a practical primary standard.
authors.affiliation: Group of Applied Physics, University of Geneva, 20 rue de l'Ecole-de-Médecine, CH-1211 Geneva 4, Switzerland.
authors.forename: Bruno
authors.initials: B
authors.lastname: Sanguinetti
authors.forename: Enrico
authors.initials: E
authors.lastname: Pomarico
authors.forename: Pavel
authors.initials: P
authors.lastname: Sekatski
authors.forename: Hugo
authors.initials: H
authors.lastname: Zbinden
authors.forename: Nicolas
authors.initials: N
authors.lastname: Gisin