Rotation of phase difference in four coupled oscillators as a regular tetrahedron form

Coupled oscillatory systems are suitable to express synchronization phenomena, and it is important to unveil nonlinear phenomena. In this study, we investigate the synchronization phenomena observed in four coupled van der Pol oscillators as a regular tetrahedron form. We observe the rotation of the phase difference between anti-phase state and asynchonization state. Furthermore, the sojourn time of the anti-phase states is calculated.