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arXiv · 2605.23755

Kondo singlet from ferromagnetic coupling: an analog of Anderson-Morel superconductivity in the magnetic channel

Ewan Scott·Yaqi Chen·Michael Turaev·Tarkan Yzeiri·Chris Hooley·Krzysztof P. Wójcik·Michał P. Kwasigroch
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Abstract

We consider magnetic impurities coupled to a conduction sea via a fully isotropic ferromagnetic spin-exchange term, the strength of which depends on the conduction-electron modes involved in the scattering. In the single-impurity case we show both analytically and numerically that there exists a parameter regime in which the conventional Kondo effect develops at low temperatures, leading to a singlet ground state. In the case of a lattice of impurities, we show that this leads to a heavy Fermi liquid state that is energetically favored over magnetic ordering in a broad parameter range. We argue that these effects are analogs of Anderson-Morel superconductivity, and discuss routes to their experimental realization.

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Ewan Scott, Yaqi Chen, Michael Turaev, Tarkan Yzeiri, Chris Hooley, Krzysztof P. Wójcik, Michał P. Kwasigroch. 2026-05-22. Kondo singlet from ferromagnetic coupling: an analog of Anderson-Morel superconductivity in the magnetic channel. https://arxiv.org/abs/2605.23755

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