First-principles study of Kondo effects in actinide- and lanthanide-based compounds

Recent advances in research on quantum materials led to discoveries of fascinating superconductors such as paramagnetic heavy fermion UTe₂, nickelates that are isostructural with high-T_c cuprates, and almost room temperature superconducting superhydrides under high pressure. A common thread of these superconductors is containing f and d electrons in lanthanide or actinide cations. However, it has been a great challenge to identify the role of the elements in the superconductivity due to its complex f and d electrons correlations. To explore the f and d entangled real systems, we employed ab-inito many-body perturbation theory combined with dynamical mean field theory (LQSGW+DMFT). In this talk, we will present the discovered Kondo effects in three materials. First, we found f-d Kondo effect in USbTe and its temperature dependence is in good agreement with ARPES. Second, we show the orbital selective Kondo effect in UTe₂, which elucidates the anomalous temperature dependence of resistivity. Finally, we will discuss the impact of f-d Kondo cloud on the superconductivity of NdNiO₂.