title: Phase shift experiments identifying Kramers doublets in a chaotic superconducting microwave billiard of threefold symmetry.
abstract: The spectral properties of a two-dimensional microwave billiard showing threefold symmetry have been studied with a new experimental technique. This method is based on the behavior of the eigenmodes under variation of a phase shift between two input channels, which strongly depends on the symmetries of the eigenfunctions. Thereby a complete set of 108 Kramers doublets has been identified by a simple and purely experimental method. This set clearly shows Gaussian unitary ensemble statistics, although the system is time-reversal invariant.
authors.affiliation: Institut für Kernphysik, Technische Universität Darmstadt, D-64289 Darmstadt, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Dembowski
authors.forename: B
authors.initials: B
authors.lastname: Dietz
authors.forename: H-D
authors.initials: HD
authors.lastname: Gräf
authors.forename: A
authors.initials: A
authors.lastname: Heine
authors.forename: F
authors.initials: F
authors.lastname: Leyvraz
authors.forename: M
authors.initials: M
authors.lastname: Miski-Oglu
authors.forename: A
authors.initials: A
authors.lastname: Richter
authors.forename: T H
authors.initials: TH
authors.lastname: Seligman