Superradiant Raman scattering with rubidium atoms in an optical cavity: Dynamical dispersive coupling and AC Stark shift effect
Phys. Rev. A 113, 043707 – Published 6 April, 2026
DOI: https://doi.org/10.1103/81q3-zyjk
Abstract
Superradiant Raman scattering of rubidium atoms was explored in the experiment [Bohnet et al., Nature (London) 484, 78 (2012)] to prove the concept of superradiant laser. However, a careful analysis of the experiment indicates that the reported distorted pulse is different from what is expected for a superradiant pulse, and the displayed spectrum seems to be broader than what is expected from the theory. To resolve these inconsistencies, we have gone beyond the effective theory employed in the experimental paper by treating the rubidium atoms as three-level systems, and coupling them with a dressed laser and an optical cavity. Our simulations show that the distorted pulse is caused by a dynamical dispersive coupling introduced by Raman-induced population transfer, and the broader spectrum is shifted due to AC Stark shift effect of the dressing laser. Our study establishes not only the consistency between the results in this experiment and those in other superradiant experiments, but also suggests that a further experiment might be required to verify the narrow spectrum of superradiant laser through the Raman transition.
