Evidence for scaling in an interfacial growth instability: The solid case

An interfacial instability driven by concentration diffusion in a solid system is studied with use of simulations based on an Ising lattice-gas model with conserved dynamics. Interfacial thermodynamic properties including the effect of surface tension are built in at the microscopic level. Finger structures evolve on a reasonable scale compared to any thermal characteristic lengths. The dynamics and universality of the growth process are studied. Evidence is presented for power-law growth, and for a scaling form in the evolution of the Fourier transform of the interface shape.