Vortex Velocity Probability Distributions in Phase Ordering Kinetics
The calculation of the point vortex velocity probability distribution function (vvpdf) is extended to a larger class of systems beyond the nonconserved TDGL model treated earlier. The range is extended to include certain anisotropic models and the conserved order parameter case. The vvpdf still satisfies scaling with large velocity tails as for the nonconserved isotropic case. It is shown that the average vortex speed can be self-consistently expressed in terms of correlation functions associated with a Gaussian auxiliary field. In the conserved order parameter case the average vortex speed decays as $t^{-1}$ compared to the $t^{-1/2}$ decay for the nonconserved case.