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arXiv · 0909.0837

Evidence of antiblockade in an ultracold Rydberg gas

Thomas Amthor·Christian Giese·Christoph S. Hofmann·Matthias Weidemüller
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Abstract

We present the experimental observation of the antiblockade in an ultracold Rydberg gas recently proposed by Ates et al. [Phys. Rev. Lett. 98, 023002 (2007)]. Our approach allows the control of the pair distribution in the gas and is based on a strong coupling of one transition in an atomic three-level system, while introducing specific detunings of the other transition. When the coupling energy matches the interaction energy of the Rydberg long-range interactions, the otherwise blocked excitation of close pairs becomes possible. A time-resolved spectroscopic measurement of the Penning ionization signal is used to identify slight variations in the Rydberg pair distribution of a random arrangement of atoms. A model based on a pair interaction Hamiltonian is presented which well reproduces our experimental observations and allows one to analyze the distribution of nearest neighbor distances.

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Thomas Amthor, Christian Giese, Christoph S. Hofmann, Matthias Weidemüller. 2009-09-04. Evidence of antiblockade in an ultracold Rydberg gas. https://doi.org/10.1103/physrevlett.104.013001

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