Counting Rare Noble Gas Atoms with a MOT

J S Briggs

T. M. Barkhudarova, G. S. Voronov, G. A. Delone +2 more

S.E. Kupriyanov, А. А. Перов

W. Jiang, K. Bailey, Z.-T. Lu +3 more

We have demonstrated that the ion current resulting from collisions between metastable krypton atoms in a magneto-optical trap can be used to precisely measure the trap loading rate. We measured both the ion current of the abundant isotope 83Kr (isotopic abundance=11%) and the single-atom counting rate of the rare isotope 85Kr (isotopic abundance∼1×10(-11)), and found the two quantities to be proportional at a precision level of 0.9%. This work results in a significant improvement in using the magneto-optical trap as an analytical tool for noble-gas isotope ratio measurements, and will benefit both atomic physics studies and applications in the earth sciences.

Fujio Shimizu

M. C. Kohler, Heiner Daerr, Peter Sahling +5 more

The determination of isotope ratios of noble-gas atoms has many applications, e.g. , in physics, nuclear-arms control, and Earth sciences. For several applications, the concentration of specific noble-gas isotopes ( e.g. , Kr and Ar) is so low that single-atom detection is highly desirable for a precise determination of the concentration. As an important step in this direction, we demonstrate the operation of a krypton atom trap trace analysis (ATTA) setup based on a magneto-optical trap (MOT) for metastable Kr atoms excited by all-optical means. Compared to other state-of-the-art techniques for preparing metastable noble-gas atoms, all-optical production is capable of overcoming limitations regarding minimal probe volume and avoiding cross-contamination of the samples. In addition, it allows for a compact and reliable setup. We identify optimal parameters of our experimental setup by employing the most abundant isotope 84 Kr, and demonstrate single-atom detection within a 3D MOT.