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Anomalous power law of quantum reversibility for classically regular dynamics

Ph. Jacquod·I. Adagideli·C. W. J. Beenakker
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Abstract

The Loschmidt Echo M(t) (defined as the squared overlap of wave packets evolving with two slightly different Hamiltonians) is a measure of quantum reversibility. We investigate its behavior for classically quasi-integrable systems. A dominant regime emerges where M(t) ~ t^{-alpha} with alpha=3d/2 depending solely on the dimension d of the system. This power law decay is faster than the result ~ t^{-d} for the decay of classical phase space densities.

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Ph. Jacquod, I. Adagideli, C. W. J. Beenakker. 2002-09-19. Anomalous power law of quantum reversibility for classically regular dynamics. https://doi.org/10.1209/epl/i2003-00289-y

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