Synchronization Phenomena Originating from Quantum Effects of Photon Fields

Synchronization phenomena in multiple polarizations through quantum effects of photon fields have been observed as superradiance. These phenomena are often observed in macroscopic and classical systems. In contrast, superradiance is cooperative spontaneous emission, that is, a synchronization phenomenon in microscopic and quantum systems. In this study, we consider two emitters in a free photon field and investigate their exact phase dynamics. By analogy with the Kuramoto model, we illustrate clearly that the interaction of synchronization in superradiance originates from spontaneous emission owing to the quantum effects of photon fields. In contrast to superradiance in-phase, subradiance in antiphase is also possible. We illustrate the parameter diagram that determines whether in-phase or antiphase oscillation occurs. In addition, we find that a temporal transition occurs from the in-phase to antiphase synchronization owing to the energy dissipation. The results of this study will stimulate further research on synchronization phenomena in microscopic and quantum systems.