https://doi.org/10.1140/epjd/e2004-00094-2
Coherent-state qubits: entanglement and decoherence
1
Institut für Theoretische Physik,
Universität Innsbruck, Technikerstrasse 25, 6020 Innsbruck, Austria
2
Research Institute for Solid State Physics and Optics,
P.O. Box 49, 1525 Budapest, Hungary
3
Research Group for Nonlinear and Quantum Optics, Hungarian Academy of
Sciences and Institute of Physics, University of Pécs,
Ifjúság út 6, 7624 Pécs, Hungary
4
Research Centre for Quantum Information, Institute of Physics,
Slovak Academy of Sciences, 845 11 Dubravská cesta 9, Bratislava, Slovakia
Corresponding author: a janos.asboth@uibk.ac.at
Received:
30
January
2004
Revised:
13
May
2004
Published online:
10
August
2004
Arbitrary superpositions of any two optical coherent states are investigated as realizations of qubits for quantum information processing. Decoherence of these coherent-state qubits is described in detail, and visualized using a suitable adaptive Bloch-sphere. The entanglement that can be created by a beam splitter from these states is quantified, and its decoherence behavior is analyzed.
PACS: 42.50.Dv – Nonclassical states of the electromagnetic field, including entangled photon states; quantum state engineering and measurements / 03.65.Ud – Entanglement and quantum nonlocality (e.g. EPR paradox, Bell's inequalities, GHZ states, etc.) / 03.67.-a – Quantum information
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2004
