Eigenvalue spectrum of the survival probability of excitation in nonradiative energy transport

The eigenvalue spectrum of the initial excitation survival probability is computed for several models of nonradiative transport in current use. It is shown that the eigenvalue spectrum is more sensitive to the finer details of the models than the survival probability. In particular, short- and long-time behaviours are clearly displayed. Based on this analysis, a simple function for the survival probability is proposed. This function represents a numerical interpolation that combines the correct short- and long-time behaviour of different theories. Monte-Carlo simulations carried out for regular lattices in one, two and three dimensions allowed the accurate numerical computation of the respective eigenvalue distributions. (C) 2000 Elsevier Science B.V. All rights reserved.