We report the numerical observation of spatiotemporal intermittency in the
critical dynamics of two-dimensional frustrated underdamped dc-driven Josep
hson junction arrays. This intermittency is due to the hopping of the syste
m among the different subcritical metastable states, which are characterize
d by domain walls separating regions with the symmetry of the ground state,
Turbulentlike domains correspond to the regions surrounding the nucleation
and decay of these domain walls, or equivalently, to the regions where vor
tex motion takes place. This intermittency is further signaled by the obser
vation of 1/f noise in the high-frequency tail of the power spectrum of the
voltage fluctuations, and by the scaling of the characteristic time scale
for front propagation with the current. A study of the ground and metastabl
e states of the system is also presented.