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arXiv · 0810.2960

Observation of collective excitation of two individual atoms in the Rydberg blockade regime

A. Gaëtan·Y. Miroshnychenko·T. Wilk·A. Chotia·M. Viteau·D. Comparat·P. Pillet·A. Browaeys·P. Grangier
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Abstract

The dipole blockade between Rydberg atoms has been proposed as a basic tool in quantum information processing with neutral atoms. Here we demonstrate experimentally the Rydberg blockade of two individual atoms separated by 4 $μ$m. Moreover, we show that, in this regime, the single atom excitation is enhanced by a collective two-atom behavior associated with the excitation of an entangled state. This observation is a crucial step towards the deterministic manipulation of entanglement of two or more atoms using the Rydberg dipole interaction.

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A. Gaëtan, Y. Miroshnychenko, T. Wilk, A. Chotia, M. Viteau, D. Comparat, P. Pillet, A. Browaeys, P. Grangier. 2008-10-16. Observation of collective excitation of two individual atoms in the Rydberg blockade regime. https://doi.org/10.1038/nphys1183

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