Numerical observation of disorder-induced anomalous kinetics in the A+A ->0 reaction

We address via numerical simulation the two-dimensional bimolecular annihil ation reaction A + A --> 0 in the presence of quenched, random impurities. Renormalization group calculations have suggested that this reaction displa ys anomalous kinetics at long times, c(A)(t) similar to at(delta-1), for ce rtain types of topological or charged species and impurities. Both the expo nent and the prefactor depend on the strength of disorder. The decay expone nts determined from our simulations agree well with the values predicted by theory. The observed renormalization of the prefactor also agrees well wit h the values predicted by theory. (C) 1999 Elsevier Science B.V. All rights reserved.