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Extended states in disordered systems: role of off-diagonal correlations

Wei Zhang·Sergio E. Ulloa
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Abstract

We study one-dimensional systems with random diagonal disorder but off-diagonal short-range correlations imposed by structural constraints. We find that these correlations generate effective conduction channels for finite systems. At a certain golden correlation condition for the hopping amplitudes, we find an extended state for an infinite system. Our model has important implications to charge transport in DNA molecules, and a possible set of experiments in semiconductor superlattices is proposed to verify our most interesting theoretical predictions.

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Wei Zhang, Sergio E. Ulloa. 2004-03-08. Extended states in disordered systems: role of off-diagonal correlations. https://doi.org/10.1103/physrevb.69.153203

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