Multiple condensates in a driven diffusive system

We investigate the nature of condensation in a driven diffusive system. Being motivated by evolving network dynamics, we consider particle dynamics with and without a pairwise repulsion. Without the pairwise repulsion, the model exhibits a condensation with a single macroscopic condensate. When the pairwise repulsion is turned on, a particle cannot hop to a site that is occupied by its own preassigned mate. Surprisingly, the pairwise repulsion breaks a macroscopic condensate into mesoscopic condensates whose number and mass scale algebraically with the system size. Our study shows that even a weak interaction plays an important role in condensation phenomena.