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arXiv · 2610.00624

The Ericson Transition in Time-Reversal Invariant Systems: Symplectically Invariant Hamiltonians

Simon Köhnes·Thomas Guhr
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Abstract

We investigate the distributions of off-diagonal scattering matrix elements and cross-sections in the Ericson regime for time-reversal invariant systems with odd spin. Within the universal Heidelberg approach we prove that Gaussian and exponential behavior is found as the leading-order term of an asymptotic expansion of the aforementioned distributions. Furthermore, the subleading-order term is derived and compared with numerical simulations.

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Simon Köhnes, Thomas Guhr. 2026-09-30. The Ericson Transition in Time-Reversal Invariant Systems: Symplectically Invariant Hamiltonians. https://arxiv.org/abs/2610.00624

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