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arXiv · 2602.15774

Correlated electronic states at a ferromagnetic oxide interface

D. Jones·A. Weh·A. Östlin·D. Braak·T. Kopp·P. Seiler·U. Eckern·L. Chioncel
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Abstract

We propose a minimal tight-binding model for the electronic interface layer of the LaAlO$_3$/SrTiO$_3$ heterostructure with oxygen vacancies. In this model, the effective carriers are subject to oxygen vacancy induced magnetic impurities. Both the effects of random on-site potentials and Zeeman-like exchange interactions between correlated carriers and magnetic impurities are taken into account. By applying the combined coherent potential approximation (CPA) and dynamical mean-field theory (DMFT) for a ferromagnetic state, we uncover a disordered Fermi-liquid regime for the majority-spins and a low energy scale which controls the transport of the minority-spin carriers, both induced by the magnetic impurities.

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D. Jones, A. Weh, A. Östlin, D. Braak, T. Kopp, P. Seiler, U. Eckern, L. Chioncel. 2026-02-17. Correlated electronic states at a ferromagnetic oxide interface. https://arxiv.org/abs/2602.15774

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