Dehybridization transition in Kondo insulators and heavy fermions

Mucio A. Continentino

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arXiv · 2505.04730

Dehybridization transition in Kondo insulators and heavy fermions

Mucio A. Continentino

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Abstract

In strongly correlated multi-band systems, like inter-metallics, heavy fermions or Kondo insulators, electron-electron and electron-phonon scattering of the electrons in the bands give rise, at finite temperatures, to a damping of these quasi-particles. This is responsible for producing an effective dehybridization between the electrons in the large conduction bands and those in the narrow, correlated band. This dehybridization effect has been used to explain the transport properties of inter-metallics and ARPES experiments in heavy fermions at sufficiently high temperatures. A new insight into this problem has been recently proposed using the theory of non-Hermitian systems. In this note, we review previous work on dehybridization in Kondo insulators and strongly correlated metals within this new perspective. For this purpose, we use a parametrization of the self-energy of the strongly correlated electrons obtained from LDA+DMFT calculations. We discuss the nature of the dehybridization transition and its consequences in the electronic spectrum and transport properties.

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Mucio A. Continentino. 2025-05-07. Dehybridization transition in Kondo insulators and heavy fermions. https://arxiv.org/abs/2505.04730

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