Time delays in anisotropic systems

• URL: http://arxiv.org/abs/2309.02059v1
• Date: Tue, 5 Sep 2023 09:00:24 GMT
• Title: Time delays in anisotropic systems
• Authors: Ulf Saalmann and Jan M. Rost
• Abstract summary: We give a criterion how to identify a potential with intrinsic symmetry which behaves like an asymmetric one if it is merely offset from the scattering center. Considering asymmetric potentials also reveals that only one version of S-matrices used in the literature generalizes to the asymmetric case.
• Score: 0.0
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: Scattering properties and time delays for general (non-symmetric) potentials in terms of the respective S-matrices are discussed paradigmatically in one dimension and in comparison to symmetric potentials. Only for the latter the Wigner and Smith time delays coincide. Considering asymmetric potentials also reveals that only one version of S-matrices used in the literature (the one with reflection coefficients on the diagonal) generalizes to the asymmetric case. Finally, we give a criterion how to identify a potential with intrinsic symmetry which behaves like an asymmetric one if it is merely offset from the scattering center.

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