|
Ultralong-range Rydberg molecules are formed by a Rydberg atom and one or more ground state atoms. The underlying binding mechanism is based on the scattering of the Rydberg electron at the polarizable ground state atom which can be treated in terms of a Fermi pseudo potential. The resulting mean-field potential leads to bound states with binding lengths of more than 100 nm and binding energies in the range of some 10 MHz [1].
We report on photoassociation spectroscopy of such molecules in an ultracold Rubidium gas. Our experimental data show different excited states of di- and triatomic molecules, whose binding energy can be reproduced by elaborate theoretical calculations [2]. The now improved spectral resolution of our experimental setup reveals further features. This comprises additional molecular states as well as a splitting of the molecular ground-state in an electric field, which can be interpreted as an indication for the rotational substructure of the molecular ground state.
[1] V. Bendkowsky et al., Nature 458, 1005 (2009) [2] V. Bendkowsky et al., W. Li et al., arXiv:0912.4058v1 |
|