Ultracold long-range van der Waals Rydberg trimer

Abstract

Rydberg molecules, Rydberg-atom or Rydberg-molecule, are an essential ingredient of cold molecular sciences. However, due to the richness of Rydberg-neutral interactions, new kinds of Rydberg molecules and binding mechanisms are still to be discovered. In this work, we predict the existence of ultra-long-range van der Waals trimers in dilute atom-gas mixtures. These are bound states of a Rydberg atom and a diatomic polar molecule mediated by the long-range van der Waals interaction. This new binding mechanism gives rise to trimers with sizes between 5-500~nm and binding energies between 2 MHz and 0.2 kHz depending on the atomic principal quantum number $n$ and orbital angular momentum $L$. We show that these molecules can be produced via two-photon photoassociation, with rates on the order of (10${}^{-13}$ - 10${}^{-11}$) cm${}^3$s${}^{-1}$ for temperatures in the range of (0.5 $\hat{I}¼K$ - 10$\hat{I}¼K$), and discuss the feasibility of observing trimer resonances.

arXiv admin note: text overlap with arXiv:2109.06411