Weyl nodes in Ce$_3$Bi$_4$Pd$_3$ revealed by dynamical mean-field theory

TL;DR

This study combines DFT and DMFT calculations to identify Weyl nodes near the Fermi energy in Ce$_3$Bi$_4$Pd$_3$, providing theoretical evidence for topological features linked to its unusual transport properties.

Contribution

First-principles calculations confirming the existence of Weyl nodes in Ce$_3$Bi$_4$Pd$_3$, supporting experimental observations and advancing understanding of its topological electronic structure.

Findings

Weyl nodes are found close to the Fermi energy.

The Kondo effect influences the angular momentum states.

Nodal lines are also present.

Abstract

Experimental studies have found unusual transport properties in Ce$_3$Bi$_4$Pd$_3$ which are potentially a consequence of the interplay between band-structure topology and electronic correlations. Based on these measurements, the existence of Weyl points in strongly renormalized, flat quasiparticle bands has been postulated. However, so far, there has been neither a direct spectroscopic observation of these, nor a calculation from first principles that would confirm their existence close to the Fermi energy. Here, we present density functional theory (DFT) and dynamical mean field theory (DMFT) calculations and study the low-energy excitations and their topological properties. We find that the Kondo effect promotes two out of the six angular momentum $J=5/2$ states, with the other four pushed to higher energies. Further, we find Weyl nodes close to the Fermi energy as previously suggested for explaining the observed giant spontaneous Hall effect in Ce$_3$Bi$_4$Pd$_3$, as well as nodal lines.