Superharmonic entrainment

FIGURE 7.11. Time series for periodically forced oscillations in the CO oxidation on a Pt(l 10) surface exhibiting sustained oscillations [34]. (a) 1 2 Subharmonic entrainment, (b) 2 1 Superharmonic entrainment, (c) 7 2 Superharmonic entrainment, (d) Quasi-periodic response. 

Externally driven limit cycles can exhibit a great variety of behaviour. Quite generally, one gets a nonlinear superposition of an internal nonlinear oscillation with an external oscillatory perturbation. Details of the resulting behaviour (including sub- and superharmonic oscillations, entrainment, quenching...) depend on both, the frequency and intensity of the applied fields and on the internal nonlinear kinetics of the considered system. 

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