We have investigated the electronic states of Au-Al-Tb quasicrystal approximants (ACs), which exhibit different magnetic ground states at low temperatures, by high-energy electron spectroscopies in the paramagnetic phase. The Tb M4,5-edge x-ray absorption and the Tb 3d-edge resonant photoemission spectroscopy (RPES) have revealed the dominant Tb3+ state with the localized 4f electrons in all samples. In addition, the hybridization between Tb 4f and 5d orbitals just below the Fermi level has been observed in the Tb 3d-edge RPES. By using the Tb L3-edge high-energy-resolution fluorescence-detected x-ray absorption spectroscopy, the different Tb 5d electronic states have been verified among the Au-Al-Tb ACs. This variation of Tb 5d states would affect the difference in the magnetic ground states of the Au-Al-Tb ACs.
Nozue et al. (Fri,) studied this question.