Multiatom dipole-dipole correlations in rubidium vapor revealed by dual-comb spectroscopy
Phys. Rev. A 114, 032801 – Published 1 September, 2026
DOI: https://doi.org/10.1103/gl56-rx8h
Abstract
Dipole-dipole interactions in atomic vapors couple the optical responses of nearby atoms and give rise to few-body correlation effects. Earlier nonlinear spectroscopic studies have identified two-atom double-quantum coherences and higher-order multiatom responses, primarily involving sum-frequency combinations of optical transitions. Here we measure the nonlinear response of rubidium vapor under conditions comparable to prior high-order studies and identify previously unreported interaction-enabled correlations. These include ground-excited pair couplings as well as three-atom correlations in which one atom evolves in a zero-quantum coherence while others evolve optically. These results demonstrate that dipole-dipole interactions give rise to more complex collective coherence structures than previously observed.
