Cavity sub- and superradiance for transversely driven atomic ensembles

Large atomic ensembles coupled to a single optical resonator mode can be steered to strongly enhanced or suppressed collective emission via phase controlled excitation. Employing the Tavis-Cummings model we find so far unreported phenomena. Using a second order cumulant expansion we predict that a homogeneously excited ensemble equally distributed between odd and even sites along the cavity mode is extremely subradiant as long as the average excitation remains below 50%, but shows pulsed emission for inversion. The combination of these two properties enables the implementation of an efficient cavity-enhanced Ramsey probing featuring a fast readout and minimal heating with particular advantages for atomic clock transitions. For continuous illumination the nonlinear atom-field interaction induces regular superradiant self-pulsing. Additionally, we observe an increased pulse delay time in comparison to an excitation through the cavity.

Automated summary

Large atomic ensembles coupled to a single optical resonator mode can exhibit strongly enhanced or suppressed collective emission by controlling the excitation phase. Using the Tavis-Cummings model, we report previously unobserved phenomena. By employing a second order cumulant expansion, we predict that a evenly excited atomic ensemble distributed along the cavity mode can be extremely subradiant when the average excitation is below 50%, but shows pulsed emission for inversion. These properties enable the implementation of an efficient cavity-enhanced Ramsey probing for atomic clock transitions with fast readout and minimal heating.