We investigate the dynamical behavior of chaotic states in two-dimensional capacitive Josephson-junction arrays (JJA) driven by uniform external ac and dc currents via numerical simulations of the resistively-shunted-junction (RSJ) model. In chaotic states the distribution functions for the fluctuating voltages in individual transverse junctions have exponential tails similar to findings for the temperature in fluid turbulence. We present a mechanism for the origin of this behavior in arrays based on the random generation and motion of vortices. We also provide evidence to argue that collectively chaotic behavior does not occur.

• Received 13 May 1994

DOI:https://doi.org/10.1103/PhysRevB.50.9376