Is. Graham et al., MODEL FOR DYNAMICS OF STRUCTURAL GLASSES, Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics, 55(3), 1997, pp. 2132-2144
We have studied, using dynamical Monte Carlo methods, a facilitated ki
netic Ising model for structural glasses. We observe stretched-exponen
tial decays (alpha relaxation) of the equilibrium spin autocorrelation
function at late times and are able to estimate accurately the corres
ponding relaxation times tau. These are found to diverge at nonzero te
mperatures following a Vogel-Fulcher law. In addition, we observe earl
y-time exponential relaxation analogous to beta relaxation of glass fo
rmers. We also examined the effective thermodynamics of systems quench
ed below this divergent temperature and subsequently heated. The resul
t is a peak in the specific heat with properties matching those of the
putative glass transition. We also find that these peaks, for differe
nt heating rates, can be rescaled to lie on a universal curve. Finally
, we studied the evolving structure factor of a frozen glass following
a rapid jump in temperature. The results are qualitatively the same a
s those for x-ray studies of heated glasses. We thus demonstrate that
this purely dynamical microscopic model can reproduce much of the phen
omenology of the glass transition and near-glass relaxation, with no t
unable parameters.