Subgap Bound States from Dynamical Impurities

Joshuah T. Heath

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arXiv · 2609.00142

Subgap Bound States from Dynamical Impurities

Joshuah T. Heath

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Abstract

We find that a single non-magnetic dynamical impurity (e.g., a low-frequency localized "vibron" mode) induces a subgap bound state in an s-wave superconductor. A closed-form solution for the bound state energy is found as a function of the vibron frequency in the elastic scattering limit, with the salient features of the bound state energies unaffected by inelastic scattering processes in the sub-THz regime. In addition to subgap features in the low-frequency local density of states, such impurities result in real space regions of reduced spectroscopic weight outside the gap peak.

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Joshuah T. Heath. 2026-08-31. Subgap Bound States from Dynamical Impurities. https://arxiv.org/abs/2609.00142

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