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arXiv · 1009.3222

Fidelity decay for local perturbations: microwave evidence for oscillating decay exponents

Bernd Köber·Ulrich Kuhl·Hans-Jürgen Stöckmann·Arseni Goussev·Klaus Richter
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Abstract

We study fidelity decay in classically chaotic microwave billiards for a local, piston-like boundary perturbation. We experimentally verify a predicted non-monotonic cross-over from the Fermi Golden Rule to the escape-rate regime of the Loschmidt echo decay with increasing local boundary perturbation. In particular, we observe pronounced oscillations of the decay rate as a function of the piston position which quantitatively agree with corresponding theoretical results based on a refined semiclassical approach for local boundary perturbations.

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Bernd Köber, Ulrich Kuhl, Hans-Jürgen Stöckmann, Arseni Goussev, Klaus Richter. 2010-09-16. Fidelity decay for local perturbations: microwave evidence for oscillating decay exponents. https://doi.org/10.1103/physreve.83.016214

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