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arXiv · 2403.11382

Topological singularity-induced Mott-like self-energy and its impact on Kondo cloud formation

Byungkyun Kang·Zachary Brown·Myoung-Hwan Kim·Hyunsoo Kim·Chul Hong Park
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Abstract

We discovered that abnormal Mott physics can emerge even in weakly correlated 4f fermions through their interplay with topological singularity. Employing ab initio many-body perturbation theory combined with dynamical mean field theory, we show that 4f electrons near the topological singular point experience strong effective Coulomb repulsion, as the hybridization channels are blocked near the singularity. As a result, Mott-like self-energy emerges, forbidding the coexistence of 4f quasiparticles and the topological singularity at the same energy level in HoPtBi, PrPtBi, and PrAlGe. The formation of 4f quasiparticles is highly dependent on the energy of topological singularity relative to the Fermi level. This effect is suggested to be responsible for the selective quantum phenomena observed between heavy fermion behavior from Kondo resonance and anomalous transport from nontrivial topological states.

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Byungkyun Kang, Zachary Brown, Myoung-Hwan Kim, Hyunsoo Kim, Chul Hong Park. 2024-03-18. Topological singularity-induced Mott-like self-energy and its impact on Kondo cloud formation. https://arxiv.org/abs/2403.11382

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