Abstract
In this presentation, interaction of stationary and pulsating localized structures of light in active and passive optical devices is studied analytically and numerically. Being close enough to each other, optical pulses interact via decaying tails. Interference between the tails can produce intensity oscillations responsible for the formation of pulse bound states. Using an asymptotic approach we derive and analyze a set of ordinary differential equations governing the slow time evolution of the parameters of individual pulses, such as their coordinates, optical and oscillation phases. Being independent of specific details of the model, the form of these "interaction equations" is determined mainly by the asymptotic behavior of the pulse tails and the symmetries of the model equations. They have a universal nature and can be used to study interaction of temporal or spatial localized structures not only in optical, but also in hydrodynamic, plasma, and even biological systems.