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Coherent control of an atomic collision in a cavity

S. Osnaghi·P. Bertet·A. Auffeves·P. Maioli·M. Brune·J. M. Raimond·S. Haroche
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Abstract

Following a recent proposal by S. B. Zheng and G. C. Guo (Phys. Rev. Lett. 85, 2392 (2000)), we report an experiment in which two Rydberg atoms crossing a non-resonant cavity are entangled by coherent energy exchange. The process, mediated by the virtual emission and absorption of a microwave photon, is characterized by a collision mixing angle four orders of magnitude larger than for atoms colliding in free space with the same impact parameter. The final entangled state is controlled by adjusting the atom-cavity detuning. This procedure, essentially insensitive to thermal fields and to photon decay, opens promising perspectives for complex entanglement manipulations.

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S. Osnaghi, P. Bertet, A. Auffeves, P. Maioli, M. Brune, J. M. Raimond, S. Haroche. 2001-05-14. Coherent control of an atomic collision in a cavity. https://doi.org/10.1103/physrevlett.87.037902

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