title: Microwave fidelity studies by varying antenna coupling.
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 Ω 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 [J. J. M. Verbaarschot, Phys. Rep. 129, 367 (1985)].
authors.affiliation: Fachbereich Physik der Philipps-Universität Marburg, D-35032 Marburg, Germany.
authors.forename: B
authors.initials: B
authors.lastname: Köber
authors.forename: U
authors.initials: U
authors.lastname: Kuhl
authors.forename: H-J
authors.initials: HJ
authors.lastname: Stöckmann
authors.forename: T
authors.initials: T
authors.lastname: Gorin
authors.forename: D V
authors.initials: DV
authors.lastname: Savin
authors.forename: T H
authors.initials: TH
authors.lastname: Seligman