Vortex Dynamics and Entropic Coulomb Forces in Ising and Potts Antiferromagnets and Ice Models
Abstract
We study the dynamics of topological defects in the triangular Ising antiferromagnet, a related model on the square lattice equivalent to the sixvertex ice model, and the threestate antiferromagnetic Potts model on the square lattice. Since each of these models has a height representation in which defects are screw dislocations, we expect them to be attracted or repelled with an entropydriven Coulomb force. In each case we show explicitly how this force is felt through local fields. We measure the force numerically, both by quenching the system to zero temperature and by measuring the motion of vortex pairs. For the threestate Potts model, we calculate both the force and the defect mobility, and find reasonable agreement with theory.
 Publication:

arXiv eprints
 Pub Date:
 February 1999
 arXiv:
 arXiv:condmat/9902200
 Bibcode:
 1999cond.mat..2200M
 Keywords:

 Condensed Matter  Statistical Mechanics