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arXiv · quant-ph/0701153

Effect of finite detection efficiency on the observation of the dipole-dipole interaction of a few Rydberg atoms

Abstract

We have developed a simple analytical model describing multi-atom signals that are measured in experiments on dipole-dipole interaction at resonant collisions of a few Rydberg atoms. It has been shown that finite efficiency of the selective field-ionization detector leads to the mixing up of the spectra of resonant collisions registered for various numbers of Rydberg atoms. The formulas which help to estimate an appropriate mean Rydberg atom number for a given detection efficiency are presented. We have found that a measurement of the relation between the amplitudes of collisional resonances observed in the one- and two-atom signals provides a straightforward determination of the absolute detection efficiency and mean Rydberg atom number. We also performed a testing experiment on resonant collisions in a small excitation volume of a sodium atomic beam. The resonances observed for 1 to 4 detected Rydberg atoms have been analyzed and compared with theory.

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I. I. Ryabtsev, D. B. Tretyakov, I. I. Beterov, V. M. Entin. 2007-10-02. Effect of finite detection efficiency on the observation of the dipole-dipole interaction of a few Rydberg atoms. https://doi.org/10.1103/physreva.76.012722

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