Dresden 2011 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
Q: Fachverband Quantenoptik und Photonik
Q 33: Quantum Information: Quantum Communication 2
Q 33.2: Vortrag
Mittwoch, 16. März 2011, 14:45–15:00, SCH A118
Probabilistic Phase-Covariant Cloning of Coherent States — •Christian R. Müller1,3, Christoffer Wittmann1,3, Petr Marek4, Radim Filip4, Mario A. Usuga2, Christoph Marquardt1,3, Ulrik L. Andersen1,2, and Gerd Leuchs1,3 — 1Max-Planck-Institut für die Physik des Lichts , Günther-Scharowsky-Str. 1 / Bau 24, 91058 Erlangen, Germany — 2Department of Physics, Technical University of Denmark, Building 309, 2800 Lyngby, Denmark — 3Institute for Optics, Information and Photonics, University Erlangen-Nuremberg, Staudtstr. 7/B2, 91058 Erlangen, Germany — 4Department of Optics, Palacký University 17, listopadu 50, 772 07 Olomouc, Czech Republic
Duplicating an unknown quantum state with high fidelity is at the heart of many quantum information and quantum communication protocols. The laws of quantum mechanics impose strict bounds on the average fidelity that can be achieved deterministically. However, in a probabilistic regime one can overcome these bounds. We present the concept of a novel probabilistic quantum cloner for coherent state alphabets based on the phase concentration scheme presented in [1]. The scheme relies solely on phase-covariant displacements and photon counting ensuring a feasible and robust implementation. We show that our scheme surpasses the deterministic approach with the hitherto highest performance for phase-covariant alphabets [2].
[1] M.A. Usuga, C.R. Müller, C. Wittmann, P. Marek, R. Filip, C. Marquardt, G. Leuchs and U.L. Andersen, Nat. Phys. 6, 767 (2010). [2] M.F. Sacchi, Phys. Rev. A 75, 042328 (2007)