Optimal multicopy asymmetric Gaussian cloning of coherent states

Journal Article · Tue May 15 04:00:00 EDT 2007 · Physical Review. A

DOI:https://doi.org/10.1103/PHYSREVA.75.052335· OSTI ID:20982504

Fiurasek, Jaromir ^[1]; Cerf, Nicolas J ^[2]

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1. Department of Optics, Palacky University, 17. listopadu 50, 77200 Olomouc (Czech Republic)
2. QuIC, Ecole Polytechnique, CP 165, Universite Libre de Bruxelles, 1050 Brussels (Belgium)

We investigate the asymmetric Gaussian cloning of coherent states which produces M copies from N input replicas in such a way that the fidelity of each copy 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 and prove the optimality of these cloners using the formalism of Gaussian completely positive maps and semidefinite programming techniques. We also present an alternative implementation of the asymmetric cloning machine where the phase-insensitive amplifier is replaced with a beam splitter, heterodyne detector, and feedforward.

• OSTI ID: 20982504
• Journal Information: Physical Review. A, Journal Name: Physical Review. A Journal Issue: 5 Vol. 75; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
AMPLIFIERS
ANNIHILATION OPERATORS
ASYMMETRY
BEAM SPLITTING
COMMUNICATIONS
EIGENSTATES
GAUSSIAN PROCESSES
INFORMATION THEORY
OPTICS