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arXiv · 2202.08582

Localization and delocalization properties in quasi-periodically driven one-dimensional disordered system

Hiroaki S. Yamada·Kensuke S. Ikeda
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Abstract

Localization and delocalization of quantum diffusion in time-continuous one-dimensional Anderson model perturbed by the quasi-periodic harmonic oscillations of $M$ colors is investigated systematically, which has been partly reported by the preliminary letter [PRE {\bf 103}, L040202(2021)]. We investigate in detail the localization-delocalization characteristics of the model with respect to three parameters: the disorder strength $W$, the perturbation strength $ε$ and the number of the colors $M$ which plays the similar role of spatial dimension. In particular, attentions are focused on the presence of localization-delocalization transition (LDT) and its critical properties. For $M\geq 3$ the LDT exists and a normal diffusion is recovered above a critical strength $ε$, and the characteristics of diffusion dynamics mimic the diffusion process predicted for the stochastically perturbed Anderson model even though $M$ is not large. These results are compared with the results of time-discrete quantum maps, i.e., Anderson map and the standard map. Further, the features of delocalized dynamics is discussed in comparison with a limit model which has no static disordered part.

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Hiroaki S. Yamada, Kensuke S. Ikeda. 2022-02-17. Localization and delocalization properties in quasi-periodically driven one-dimensional disordered system. https://doi.org/10.1103/physreve.105.054201

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