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Anomalous diffusion through coupling to a fractal environment: Microscopic derivation of the "whip-back" effect

E. Lutz
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Abstract

Two models for quantum Brownian motion - the Oscillator Bath (OB) model and the Random-Band-Matrix (RBM) model - are compared and a relation between the spectral density function I(w) and the variance (Vab)^2 is established. The extension to a fractal environment is then considered and the microscopic origin of anomalous diffusion is discussed. In particular, it is shown that the asymptotic behavior of the normalized velocity auto-correlation function (VACF) is entirely determined by the band form factor. This allows for a microscopic derivation of the "whip-back" effect.

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E. Lutz. 2000-04-04. Anomalous diffusion through coupling to a fractal environment: Microscopic derivation of the "whip-back" effect. https://doi.org/10.1209/epl%2Fi2001-00240-x

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