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

Alpha Gaëtan (1) , Yevhen Miroshnychenko (1) , Tatjana Wilk (1) , Amodsen Chotia (2) , Matthieu Viteau (2) , Daniel Comparat (2) , Pierre Pillet (2) , Antoine Browaeys (1) , Philippe Grangier (1)

1 Laboratoire Charles Fabry de l'Institut d'Optique / Optique quantique
2 LAC - Laboratoire Aimé Cotton

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 $\mu$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.

Domaines: Physique Quantique [quant-ph]

Alpha Gaëtan, Yevhen Miroshnychenko, Tatjana Wilk, Amodsen Chotia, Matthieu Viteau, et al.. Observation of collective excitation of two individual atoms in the Rydberg blockade regime. Nature Physics, 2009, 5, pp.115-118. ⟨10.1038/nphys1183⟩. ⟨hal-00508999⟩