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arXiv · 2302.14366

$\mathbb{Z}_2$ Non-Hermitian skin effect in equilibrium heavy-fermions

Shin Kaneshiro·Tsuneya Yoshida·Robert Peters
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Abstract

We demonstrate that a correlated equilibrium $f$-electron system with time-reversal symmetry can exhibit a $\mathbb{Z}_2$ non-Hermitian skin effect of quasi-particles. In particular, we analyze a two-dimensional periodic Anderson model with spin-orbit coupling by combining the dynamical mean-field theory (DMFT) and the numerical renormalization group. We prove the existence of the $\mathbb{Z}_2$ skin effect by explicitly calculating the topological invariant and show that spin-orbit interaction is essential to this effect. Our DMFT analysis demonstrates that the $\mathbb{Z}_2$ skin effect of quasi-particles is reflected on the pseudo-spectrum. Furthermore, we analyze temperature effects on this skin effect using the generalized Brillouin zone technique, which clarifies that the skin modes are strongly localized above the Kondo temperature.

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Shin Kaneshiro, Tsuneya Yoshida, Robert Peters. 2023-02-28. $\mathbb{Z}_2$ Non-Hermitian skin effect in equilibrium heavy-fermions. https://arxiv.org/abs/2302.14366

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