Tunneling of two interacting atoms from excited states

We consider tunneling of two interacting atoms with an even spatial symmetry. The atoms are prepared in two lowest excited states with respect to relative and center-of-mass motions. We observe monotonic and non-monotonic dependence of the decay rate of the total probability as a function of the interatomic coupling strength $g$. We find a transition from uncorrelated to correlated pair tunneling as a function of $g$ and an external trap barrier. The similar system has been investigated for two interacting $^6$Li atoms in the deterministic Heidelberg experiment.