ORDERING KINETICS IN THE 2-DIMENSIONAL CLASSICAL COULOMB GAS OF HALF-INTEGER CHARGES ON A SQUARE LATTICE - TEMPERATURE-DEPENDENT GROWTH ANDROUGHENING TRANSITION

The ordering kinetics in the Coulomb gas (CG) of half-integer charges is investigated via Monte Carlo simulations. Because of the long range Coulomb interaction, the phase ordering of this system is governed by an activation energy barrier with a logarithmic dependence on the dom ain size. This results in a genuine temperature-dependent growth and a roughening transition of the domain-wall morphology above T-R similar or equal to 0.09 +/- 0.01. An analytical argument with numerical veri fication indicates that the classical CG of half-integer charges belon gs to a new universality class from the viewpoint of Lai et al.'s clas sification of ordering kinetics [Phys. Rev. B 37, 9481 (1988)].