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Stability of quantum motion in regular systems: a uniform semiclassical approach

Wen-ge Wang·G. Casati·Baowen Li
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Abstract

We study the stability of quantum motion of classically regular systems in presence of small perturbations. Onthe base of a uniform semiclassical theory we derive the fidelity decay which displays a quite complexbehaviour, from Gaussian to power law decay $t^{-α}$ with $1 \le α\le 2$. Semiclassical estimates are given for the time scales separating the different decaying regions and numerical results are presented which confirm our theoretical predictions.

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Wen-ge Wang, G. Casati, Baowen Li. 2007-01-19. Stability of quantum motion in regular systems: a uniform semiclassical approach. https://doi.org/10.1103/physreve.75.016201

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