2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/27484The homogeneous ordered state transforms into a polydomain state via a nucleation mechanism in two-dimensional lattice gas if the particle jumps are biased by an external field $E$. A simple phenomenological model is used to describe the time evolution of a circular interface separating the ordered regions. It is shown that the area of a domain increases if its radius exceeds a critical value proportional to $1/E$ which agrees qualitatively with Monte Carlo simulations.REVTEX, 3 twocolumn pages including a PS figureCondensed Mattertext