REGIME INTERPRETATION OF ANOMALOUS VORTEX DYNAMICS IN 2D SUPERCONDUCTORS

Low-frequency dynamic impedance [sigma(-1)(omega,T)=(sigma(1) + i sigm a(2))(-1)] measurements on Josephson junction arrays found that sigma( 1) similar to /In omega/, sigma(2) similar to const. This implies anom alously sluggish;vortex mobilities mu(V)(omega) similar to sigma(1)(-1 ), and is in conflict with general dynamical scaling expressions. We-c alculate (a) sigma(omega,T) by real-space vortex.scaling and (b) mu(V) (omega) using Mori's formalism for a screened Coulomb gas. We find, in addition to the usual critical (large-omega) and hydrodynamic (low-om ega) regimes, a new intermediate-frequency scaling regime into which t he experimental data fall. This resolves the above mentioned conflict and makes explicit predictions for the scaling form of sigma(omega,T).