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arXiv · 1912.07395

Beyond Born-Oppenheimer approximation in ultracold atomic collisions

Eberhard Tiemann·Philipp Gersema·Kai K. Voges·Torsten Hartmann·Alessandro Zenesini·Silke Ospelkaus
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Abstract

We report on deviations beyond the Born-Oppenheimer approximation in the potassium inter-atomic potentials. Identifying three up-to-now unknown $d$-wave Feshbach resonances, we significantly improve the understanding of the $^{39}$K inter-atomic potentials. Combining these observations with the most recent data on known inter- and intra-isotope Feshbach resonances, we show that Born-Oppenheimer corrections can be determined from atomic collisional properties alone and that significant differences between the homo- and heteronuclear case appear.

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Eberhard Tiemann, Philipp Gersema, Kai K. Voges, Torsten Hartmann, Alessandro Zenesini, Silke Ospelkaus. 2019-12-16. Beyond Born-Oppenheimer approximation in ultracold atomic collisions. https://doi.org/10.1103/physrevresearch.2.013366

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