Synchronization and resonance in a driven system of coupled oscillators

We study the noise effects in a driven system of globally coupled oscillato rs, with particular attention to the interplay between driving and noise. T he self-consistency equation for the order parameter, which measures the co llective synchronization of the system, is derived; it is found that the to tal order parameter decreases monotonically with noise, indicating overall suppression of synchronization. Still, for large coupling strengths, there exists an optimal noise level at which the periodic (ac) component of the o rder parameter reaches its maximum. The response of the phase velocity is a lso examined and found to display resonance behavior. [S1063-651X(99)14310- 1].