Kondo resonance in PrTi2Al20: Photoemission spectroscopy and single-impurity Anderson model calculations

The Kondo resonance at the Fermi level is well established for the electronic structure of Ce (4f(1) electron) and Yb (4f(1) hole)-based systems. In this work, we report complementary experimental and theoretical studies on the Kondo resonance in the Pr-based 4f(2) system, PrTi2Al20. Using Pr 3d-4f resonant photoemission spectroscopy and single-impurity Anderson model (SIAM) calculations including the full multiplets of Pr ions, we show that a 4f(2) system can also give rise to a Kondo resonance at the Fermi level. The Kondo resonance peak is experimentally observed through a final-state multiplet-dependent resonance and is reproduced with properly tuned hybridization strength in SIAM calculations.