Long-lived optical superradiance in the regime of multipulse excitation

The multipulse regime of excitation of optical superradiance in both two- and multilevel systems is theoretically investigated for the first time. It is demonstrated that this regime is the generalization of the triggering regime of superradiance excitation. We derive kinetic equations governing the dynamics of polarization waves and the population grating in a system of excited particles interacting with each other through the common field of emitted photons. The possibility of long-lived optical superradiance in impurity crystals doped with rare-earth ions is demonstrated.