Strong correlation effect in DFT-based topological characterization of Weyl-Kondo semimetals*

It is commonly accepted that density functional theory (DFT) inaccurately describes materials for which the strong correlation effect (SCE), characterized by a strong inter-electronic Hubbard U, is prominent. This is typically the case for d- and f-electron systems. However, recent advances in DFT development at the meta-GGA (meta-generalized gradient approximation) level have demonstrated significantly improved descriptions of the electronic and magnetic properties of high-T_C cuprate superconductors without explicitly involving U.¹ Naturally, one asks whether such improvements are present for other types of correlated materials and other material properties. In this work, we use DFT to study the electronic and topological properties of the recently proposed Weyl-Kondo semimetal (WKSM) Ce₃Pd₃Bi₄.² We model the system with and without valence f-electrons to identify the role that the SCE plays when determining bulk band topology. Additionally, we consider different density functionals and discuss the remaining obstacles in achieving accurate first-principles characterization of interacting topological materials.

References:
¹Furness et al., Commun Phys 1, 11 (2018).
²Lai et al., PNAS 115, 1, 93-97 (2018).