EFFECT OF TEMPORAL NOISE ON THE SINGLE-ELECTRON TRANSPORT IN LONG MOLECULES

We analyze single-electron or exciton transport in long molecules in t he presence of both static disorder and temporal noise both of which i nevitably exist in biological systems. The equations for the density m atrix are derived within an approximation that the temporal noise of t ransition amplitudes is not correlated. Our model predicts that while in the short-time limit the transport remains coherent, for sufficient ly long time the temporal noise causes destruction of the phase cohere nce, and a crossover from coherent to diffusive transport takes place. This effect leads to the power-law asymptotic behavior of the transmi ssion coefficient with the exponent depending on the effective dimensi onality of the molecule. (C) 1998 Published by Elsevier Science B.V. A ll rights reserved.