title: Experimental evidence of anomalous phase synchronization in two diffusively coupled Chua oscillators.
abstract: We study the transition to phase synchronization in two diffusively coupled, nonidentical Chua oscillators. In the experiments, depending on the used parameterization, we observe several distinct routes to phase synchronization, including states of either in-phase, out-of-phase, or antiphase synchronization, which may be intersected by an intermediate desynchronization regime with large fluctuations of the frequency difference. Furthermore, we report the first experimental evidence of an anomalous transition to phase synchronization, which is characterized by an initial enlargement of the natural frequency difference with coupling strength. This results in a maximal frequency disorder at intermediate coupling levels, whereas usual phase synchronization via monotonic decrease in frequency difference sets in only for larger coupling values. All experimental results are supported by numerical simulations of two coupled Chua models.
authors.affiliation: Instrument Division, Indian Institute of Chemical Biology, Jadavpur, Kolkata 700032, India. skdana@iicb.res.in
authors.forename: Syamal Kumar
authors.initials: SK
authors.lastname: Dana
authors.forename: Bernd
authors.initials: B
authors.lastname: Blasius
authors.forename: Jürgen
authors.initials: J
authors.lastname: Kurths
mesh_terms: D000465:Algorithms; D001683:Biological Clocks / Q000502:physiology*; D003198:Computer Simulation; D005246:Feedback / Q000502:physiology*; D008954:Models, Biological; D017711:Nonlinear Dynamics