Dynamic scaling for two-dimensional superconductors, Josephson-junction arrays, and superfluids

The value of the dynamic critical exponent {ital z} is studied for two-dimensional superconducting, superfluid, and Josephson junction array systems in zero magnetic field via the Fisher-Fisher-Huse dynamic scaling. We find z{approx_equal}5.6{plus_minus}0.3, a relatively large value indicative of nondiffusive dynamics. Universality of the scaling function is tested and confirmed for the thinnest samples. We discuss the validity of the dynamic scaling analysis as well as the previous studies of the Kosterlitz-Thouless-Berezinskii transition in these systems, the results of which seem to be consistent with simple diffusion (z=2). Further studies are discussed and encouraged. {copyright} {ital 1999} {ital The American Physical Society}