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arXiv · 0811.0264

Two-photon gateway in one-atom cavity quantum electrodynamics

A. Kubanek·A. Ourjoumtsev·I. Schuster·M. Koch·P. W. H. Pinkse·K. Murr·G. Rempe
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Abstract

Single atoms absorb and emit light from a resonant laser beam photon by photon. We show that a single atom strongly coupled to an optical cavity can absorb and emit resonant photons in pairs. The effect is observed in a photon correlation experiment on the light transmitted through the cavity. We find that the atom-cavity system transforms a random stream of input photons into a correlated stream of output photons, thereby acting as a two-photon gateway. The phenomenon has its origin in the quantum anharmonicity of the energy structure of the atom-cavity system. Future applications could include the controlled interaction of two photons by means of one atom.

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A. Kubanek, A. Ourjoumtsev, I. Schuster, M. Koch, P. W. H. Pinkse, K. Murr, G. Rempe. 2008-11-03. Two-photon gateway in one-atom cavity quantum electrodynamics. https://doi.org/10.1103/physrevlett.101.203602

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