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Superballistic spreading of wave packets

L. Hufnagel·R. Ketzmerick·T. Kottos·T. Geisel
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Abstract

We demonstrate for various systems that the variance of a wave packet $M(t)\propto t^ν$, can show a {\it superballistic} increase with $2<ν\le3$, for parametrically large time intervals. A model is constructed which explains this phenomenon and its predictions are verified numerically for various disordered and quasi-periodic systems.

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L. Hufnagel, R. Ketzmerick, T. Kottos, T. Geisel. 2001-08-28. Superballistic spreading of wave packets. https://doi.org/10.1103/physreve.64.012301

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