Synchronization and clustering in coupled parametrically excited oscillators with small mismatch

In this study, we investigate synchronization of parametrically excited van der Pol oscillators with small mismatch. In the case of two subcircuits, we confirm that the two subcircuits are synchronized at in-phase state when the adding mismatch is small. By increasing the small mismatch, we observe unsynchronous phenomena. Furthermore, we apply this circuit model to ten coupled oscillators as random network model with hub.