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arXiv · 2505.09573

Experimental study of the distributions of off-diagonal scattering-matrix elements of quantum graphs with symplectic symmetry

Jiongning Che·Nils Gluth·Simon Köhnes·Thomas Guhr·Barbara Dietz
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Abstract

We report on experimental studies of the distribution of the off-diagonal elements of the scattering matrix of open microwave networks with symplectic symmetry and a chaotic wave dynamics. These consist of two geometrically identical subgraphs with unitary symmetry described by complex conjugate Hamiltonians, that are coupled by a pair of bonds. The results are compared to random-matrix theory predictions obtained on the basis of the Heidelberg approach for the scattering matrix of open quantum-chaotic systems. We demonstrate that deviations from random-matrix theory predictions observed in the distributions may be attributed to the fact that the subgraphs are not fully connected.

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Jiongning Che, Nils Gluth, Simon Köhnes, Thomas Guhr, Barbara Dietz. 2025-07-27. Experimental study of the distributions of off-diagonal scattering-matrix elements of quantum graphs with symplectic symmetry. https://doi.org/10.1103/qm3x-jvyw

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