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arXiv · 0801.0513

Quantum Diffusion and Localization in Disordered Electronic Systems

P. R. Wells Jr.·J. d'Albuquerque e Castro·S. L. A. de Queiroz
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Abstract

The diffusion of electronic wave packets in one-dimensional systems with on-site, binary disorder is numerically investigated within the framework of a single-band tight-binding model. Fractal properties are incorporated by assuming that the distribution of distances $\ell$ between consecutive impurities obeys a power law, $P(\ell) \sim \ell^{-α}$. For suitable ranges of $α$, one finds system-wide anomalous diffusion. Asymmetric diffusion effects are introduced through the application of an external electric field, leading to results similar to those observed in the case of photogenerated electron-hole plasmas in tilted InP/InGaAs/InP quantum wells.

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P. R. Wells Jr., J. d'Albuquerque e Castro, S. L. A. de Queiroz. 2008-07-07. Quantum Diffusion and Localization in Disordered Electronic Systems. https://doi.org/10.1103/physrevb.78.035102

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