Dynamic scaling theory of the Kosterlitz-Thouless-Berezinskii transition: ubiquitous finite size effects

A numerical study of the neutral two-dimensional (2D) lattice Coulomb gas is performed to examine dynamic scaling, finite size effects, and the dynamic critical exponent $z$ of the Kosterlitz-Thouless-Berezinskii transition. By studying large system sizes ($L=100$), we show $z=2.0 \pm0.2$ using Fisher-Fisher-Huse (FFH) scaling. We also present evidence that the vortex correlation length is finite below the transition temperature, in contrast to conventional wisdom. Finally, we conclude that previous findings for a variety of experimental systems that $z\simeq 5.6$ using FFH scaling indicates that finite size effects are ubiquitous in 2D superconductors and Josephson Junction Arrays.