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arXiv · 1006.3478

Microwave fidelity studies by varying antenna coupling

B. Köber·U. Kuhl·H. -J. Stöckmann·T. Gorin·D. V. Savin·T. H. Seligman
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Abstract

The fidelity decay in a microwave billiard is considered, where the coupling to an attached antenna is varied. The resulting quantity, coupling fidelity, is experimentally studied for three different terminators of the varied antenna: a hard wall reflection, an open wall reflection, and a 50 Ohm load, corresponding to a totally open channel. The model description in terms of an effective Hamiltonian with a complex coupling constant is given. Quantitative agreement is found with the theory obtained from a modified VWZ approach [Verbaarschot et al, Phys. Rep. 129, 367 (1985)].

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B. Köber, U. Kuhl, H. -J. Stöckmann, T. Gorin, D. V. Savin, T. H. Seligman. 2010-09-16. Microwave fidelity studies by varying antenna coupling. https://doi.org/10.1103/physreve.82.036207

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