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Sensitivity of Quantum Motion for Classically Chaotic Systems

Giuliano Benenti·Giulio Casati
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Abstract

We discuss the behavior of fidelity for a classically chaotic quantum system in the metallic regime. We show the existence of a critical value of the perturbation below which the exponential decay of fidelity is determined by the width of the Breit-Wigner distribution and above which the quantum decay follows the classical one which is ruled by the Lyapunov exponent. The independence of the decay {\it rate} from the perturbation strength derives from the similarity of the quantum and classical relaxation process inside the Heisenberg time scale.

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Giuliano Benenti, Giulio Casati. 2001-12-10. Sensitivity of Quantum Motion for Classically Chaotic Systems. https://doi.org/10.1103/physreve.65.066205

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