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arXiv · 0806.2583

Avoided crossings between bound states of ultracold Cesium dimers

Jeremy M. Hutson·Eite Tiesinga·Paul S. Julienne
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Abstract

We present an efficient new computational method for calculating the binding energies of the bound states of ultracold alkali-metal dimers in the presence of magnetic fields. The method is based on propagation of coupled differential equations and does not use a basis set for the interatomic distance coordinate. It is much more efficient than the previous method based on a radial basis set and allows many more spin channels to be included. This is particularly important in the vicinity of avoided crossings between bound states. We characterize a number of different avoided crossings in Cs_2 and compare our converged calculations with experimental results. Small but significant discrepancies are observed in both crossing strengths and level positions, especially for levels with l symmetry (rotational angular momentum L=8). The discrepancies should allow the development of improved potential models in the future.

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Jeremy M. Hutson, Eite Tiesinga, Paul S. Julienne. 2008-06-16. Avoided crossings between bound states of ultracold Cesium dimers. https://doi.org/10.1103/physreva.78.052703

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