Ultralong-range Rydberg bi-molecules

TL;DR

This paper predicts the formation of ultralong-range Rydberg bi-molecules from collisions between polar molecules and Rydberg states, with potential applications in microwave spectroscopy and studying long-range interactions.

Contribution

It introduces a theoretical model for Rydberg bi-molecules formed from nitric oxide collisions, including their properties and spectroscopic features.

Findings

Rydberg bi-molecules have GHz energies and kilo-Debye dipole moments.

Rotational constants are in the MHz range, enabling microwave spectroscopy.

Significant orientation of NO dipoles can be achieved.

Abstract

We predict that ultralong-range Rydberg bi-molecules form in collisions between polar molecules in cold and ultracold settings. The collision of $\Lambda$-doublet nitric oxide (NO) with long-lived Rydberg NO($nf$, $ng$) molecules forms ultralong-range Rydberg bi-molecules with GHz energies and kilo-Debye permanent electric dipole moments. The Hamiltonian includes both the anisotropic charge-molecular dipole interaction and the electron-NO scattering. The rotational constant for the Rydberg bi-molecules is in the MHz range, allowing for microwave spectroscopy of rotational transitions in Rydberg bi-molecules. Considerable orientation of NO dipole can be achieved. The Rydberg molecules described here hold promise for studies of a special class of long-range bi-molecular interactions.