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arXiv · 1806.02598

Effects of scarring on quantum chaos in disordered quantum wells

J. Keski-Rahkonen·P. J. J. Luukko·S. Åberg·E. Räsänen
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Abstract

The suppression of chaos in quantum reality is evident in quantum scars, i.e., in enhanced probability densities along classical periodic orbits, providing opportunities in controlling quantum transport in nanoscale quantum systems. Here, we focus on the energy level statistics of perturbed two-dimensional quantum systems exhibiting recently discovered, strong perturbation-induced quantum scarring. In particular, we study the effect of local perturbations and an external magnetic field on the eigenvalue statistics and scarring. Energy spectra are analyzed to investigate the chaoticity of the quantum system in the context of the Bohigas-Giannoni-Schmidt conjecture. We demonstrate that perturbation-induced scarring is strong in classically fully chaotic systems that, however, represent mixed eigenvalue statistics in the quantum case.

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J. Keski-Rahkonen, P. J. J. Luukko, S. Åberg, E. Räsänen. 2018-06-07. Effects of scarring on quantum chaos in disordered quantum wells. https://doi.org/10.1088/1361-648x/aaf9fb

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