Origin of the Transition Inside the Desynchronized State in Coupled Chaotic Oscillators

We investigate the origin of the transition inside the desynchronization state via phase jumps in coupled chaotic oscillators. We claim that the transition is governed by type-I intermittency in the presence of noise whose characteristic relation is $<l > \propto \exp(\alpha|\epsilon_t -\epsilon|^{3/2})$ for $\epsilon_t -\epsilon <0$ and $<l > \propto (\epsilon_t -\epsilon)^{-1/2}$ for $\epsilon_t -\epsilon >0$, where $<l>$ is the average length of the phase locking state and $\epsilon$ is the coupling strength. To justify our claim we obtain analytically the tangent point, the bifurcation point, and the return map which agree well with those of the numerical simulations.