Low-temperature nucleation in a kinetic Ising model under different stochastic dynamics with local energy barriers
Abstract
Using both analytical and simulational methods, we study low-temperature nucleation rates in kinetic Ising lattice-gas models that evolve under two different Arrhenius dynamics that interpose between the Ising states a transition state representing a local energy barrier. The two dynamics are the transition-state approximation [T. Ala-Nissila, J. Kjoll, and S. C. Ying, Phys. Rev. B 46, 846 (1992)] and the one-step dynamic [H. C. Kang and W. H. Weinberg, J. Chem. Phys. 90, 2824 (1989)]. Even though they both obey detailed balance and are here applied to a situation that does not conserve the order parameter, we find significant differences between the nucleation rates observed with the two dynamics, and between them and the standard Glauber dynamic [R. J. Glauber, J. Math. Phys. 4, 294 (1963)], which does not contain transition states. Our results show that great care must be exercised when devising kinetic Monte Carlo transition rates for specific physical or chemical systems.
Cite
@article{arxiv.cond-mat/0402537,
title = {Low-temperature nucleation in a kinetic Ising model under different stochastic dynamics with local energy barriers},
author = {Gloria M. Buendia and Per Arne Rikvold and Kyungwha Park and M. A. Novotny},
journal= {arXiv preprint arXiv:cond-mat/0402537},
year = {2007}
}
Comments
14 pages RevTex, 6 embedded figures. Minor revisions. J. Chem. Phys., in press