We analyze the kinetics of domain growth for a Hamiltonian which models the formation of ordered monolayers of H on a (110) surface of Fe. Monte Carlo simulations using particle exchange dynamics have been used to study the unstable growth of domains for coverages θ = 0.5 (for which the stable phase is (2 × 1)) and θ = 0.666 (for which the stable phase is (3 × 1)). In the former case, the ground state degeneracy is p = 2 and the average domain size follows an Allen-Cahn power law with an exponent x = 1 2. In the latter case we find a much slower growth due to interface diffusion. However, we cannot characterize this growth by a simple power law behavior for the time regime investigated. There are also some indications that the growth in this phase could be anisotropic.
Bibliographical noteFunding Information:
We would Iike to thank Dr. Ed Gawhnski and Dr. Martin Grant for some useful and stimulating discussions. J.V. is supported by CIRIT (Generalitat de Catalunya). This work is supported by ONR Grant No. N~Ol4-83-K-0382.