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Phase shift experiments identifying Kramers doublets in a chaotic superconducting microwave billiard of threefold symmetry

C. Dembowski·B. Dietz·H. -D. Graef·A. Heine·F. Leyvraz·M. Miski-Oglu·A. Richter·T. H. Seligman
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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.

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C. Dembowski, B. Dietz, H. -D. Graef, A. Heine, F. Leyvraz, M. Miski-Oglu, A. Richter, T. H. Seligman. 2003-01-09. Phase shift experiments identifying Kramers doublets in a chaotic superconducting microwave billiard of threefold symmetry. https://doi.org/10.1103/physrevlett.90.014102

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