Metal-insulator transition in a CuO chain created by Kondo interaction

Todor M. Mishonov; Albert M. Varonov; Kaloian D. Lozanov

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arXiv · 2509.25251

Metal-insulator transition in a CuO chain created by Kondo interaction

Todor M. Mishonov·Albert M. Varonov·Kaloian D. Lozanov

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Abstract

Over twenty years ago Alexei Abrikosov [A.A. Abrikosov, Metal-insulator transition in layered cuprates (SDW model), Physica C: Supercond. Vol. 391, 2, 147-159 (2003)] considered the Spin-Density-Waves (SDW) model for the metal-insulator transition in layered cuprates. In one of those cuprates, YBa$_2$Cu$_3$O$_{7-\delta}$, there are one-dimensional (1D) CuO chains of copper and oxygen ions. In the present work we consider the metal-insulator transition in the model case of a 1D CuO chain in the regime of half-filling of the band. Our model is essentially the same, but as an exchange interaction causing the metal-insulator transition, we consider Kondo-Zener two-electron exchange, which successfully describes many of the electronic properties of the layered cuprates.

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Todor M. Mishonov, Albert M. Varonov, Kaloian D. Lozanov. 2025-09-27. Metal-insulator transition in a CuO chain created by Kondo interaction. https://arxiv.org/abs/2509.25251

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