Nondestructive Detection of Polar Molecules via Rydberg Atoms

A highly sensitive, general, and preferably nondestructive technique to detect polar molecules would greatly advance a number of fields, in particular quantum science with cold and ultracold molecules. Here, we propose using resonant energy transfer between molecules and Rydberg atoms to detect molecules. Based on an energy transfer cross section of $>{10}^{-6}$cm${}^2$ for sufficiently low collision energies, a near unit efficiency non-destructive detection of basically any polar molecule species in a well defined internal state should be possible.