Topological Filtering and Emergent Kondo Scale

Ryosuke Yoshii; Rio Oto

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arXiv · 2603.23403

Topological Filtering and Emergent Kondo Scale

Ryosuke Yoshii·Rio Oto

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Abstract

We study the Kondo effect induced by a topological soliton in a one-dimensional Dirac system with the sign-changing mass term. The soliton hosts a localized zero mode whose spatially extended wavefunction leads to a momentum-dependent exchange coupling with itinerant electrons. We show that this structure generates a nontrivial form factor that suppresses high-energy scattering processes, resulting in an energy-dependent effective Kondo coupling. As a consequence, the real-space structure of the soliton directly controls the emergent Kondo scale. This work establishes a mechanism by which topological defects control many-body energy scales through their wavefunction structure, suggesting a general principle for engineering many-body energy scales via topology.

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Ryosuke Yoshii, Rio Oto. 2026-03-24. Topological Filtering and Emergent Kondo Scale. https://arxiv.org/abs/2603.23403

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