Effect of thermal fluctuations on the coarsening dynamics

LEOPOLDO R. GÓMEZ; ENRIQUE M. VALLÉS; DANIEL A. VEGA

PHYSICA A - STATISTICAL AND THEORETICAL PHYSICS

Año: 2007 vol. 386 p. 648 - 654

0378-4371

The dynamics of ordering in a 2D hexagonal system was investigated through the Cahn–Hilliard–Cook model. At low thermal noise amplitudes, pinning forces acting on grain boundaries dominate the dynamics and the coarsening evolves logarithmically in time. As noise amplitude increases, fluctuations becomes large enough to unlock dislocations located along grain boundaries and the grain boundary motion is driven by curvature. The grain boundary relaxation leads to a grain structure with Lifshitz’s configurations. In this case the dynamic is also logarithmic as a consequence of the pinning of triple points.