Uni-directional synchronization and frequency difference locking induced by a heteroclinic ratchet

A system of four coupled oscillators that exhibits unusual synchronization phenomena has been ana- lyzed. Existence of a one-way heteroclinic network, called heteroclinic ratchet, gives rise to uni-directional (de)synchronization between certain groups of cells. Moreover, we show that locking in frequency differ- ences occur when a small white noise is added to the dynamics of oscillators.