Recoil-induced symmetry breaking in superfluorescence

We extend the mean-field theory of superfluorescence for a gas system in a bidirectional ring cavity configuration to include atomic center-of-mass motion. This analysis shows that, whereas for stationary atoms the radiation evolution is independent of the sign of the detuning from atomic resonance, for atoms moving under the action of the radiative forces the radiation evolution is strongly dependent on the sign of the detuning. This previously unpredicted behavior is due to the spontaneous formation of a ponderomotive potential simultaneous with the superfluorescent radiation pulses. This potential causes the formation of a strong density grating in the atomic sample.