Agradecimientos:
AS. was partially supported by MEC (Spain)/Fulbright, by DGICyT (Spain) through project PB92-0248, and by the European Union Human Capital and Mobility Programme through Contract No. ERBCHRXCT930413. ED.-A was supported by Universidad Complutense through project PRI61193-4811. G.P.B. gratefully acknowledges partial support from Linkage Grant No. 93-1602 from NATO Special Programme Panel on Nanotechnology. Work at Los Alamos is performed under the auspices of the U.S. Department of Energy.
We propose an explanation of the bands of extended states appearing in random one-dimensional models
with correlated disorder, focusing on the continuous random-dimer model [A. Sanchez, E. Macia, and
F. Dominguez-Adame, Phys. Rev. B 49, 147 (1994)]. We show exWe propose an explanation of the bands of extended states appearing in random one-dimensional models
with correlated disorder, focusing on the continuous random-dimer model [A. Sanchez, E. Macia, and
F. Dominguez-Adame, Phys. Rev. B 49, 147 (1994)]. We show exactly that the transmission coefficient at the
resonant energy is independent of the number of host sites between two consecutive dimers. This allows us to
understand why there are bands of extended states for every realization of the model as well as the dependence
of the bandwidths on the concentration. We carry out a perturbative calculation that sheds more light on the
above results. In the conclusion we discuss generalizations of our results to other models and possible applications
which arise from insight into this problem.[+][-]