Photon sorters and QND detectors using single photon emitters
QUANTOP, Niels Bohr Institute, University of Copenhagen - DK-2100 Copenhagen Ø, Denmark, EU
2 Max Planck Institute for Dynamics and Self-Organization (MPIDS) - D-30777 Göttingen, Germany, EU
3 Department of Physics, Harvard University - Cambridge, MA 02138, USA
Accepted: 1 February 2012
We discuss a new method for realizing number-resolving and non-demolition photo detectors by strong coupling of light to individual single photon emitters, which act as strong optical non-linearities. As a specific application we show how these elements can be integrated into an error-proof Bell state analyzer, whose efficiency exceeds the best possible performance with linear optics even for a modest atom-field coupling. The methods are error-proof in the sense that every detection event unambiguously projects the photon state onto a Fock or Bell state and imperfections only result in reduced success probability, not in wrong results.
PACS: 03.67.-a – Quantum information / 42.50.Ex – Optical implementations of quantum information processing and transfer / 42.50.Pq – Cavity quantum electrodynamics; micromasers
© EPLA, 2012