Signature of the Meyer-Neldel rule on the correlated barrier-hopping model

In this study, a modified model for bipolaron correlated barrier hopping (CBH) is proposed, since the usual bipolaron CBH model has been found to be inconsistent with experimental data for ac conductivity for chalcogenide glasses at high temperatures. The present model is based on the existence of a focal point when the experimental data are extrapolated to high temperatures on the sigma(omega)-1/T plot. The correct analysis must introduce the concept of the Meyer-Neldel rule in the expression of the relaxation time. The results of the present model are in quantitative agreement with reported ac conductivity measurements. (C) 2002 American Institute of Physics.