Electronic Structure of Trivalent Compound EuPd3 Studied by Soft X-ray Angle-resolved Photoemission Spectroscopy

EuPd3 is a rare Eu-based compound, whose Eu ions are in a trivalent state. The electronic structure of EuPd3 was investigated by angle-resolved photoemission spectroscopy (ARPES) using soft x rays. Eu3+ components arising from the 4f(5) final state multiplet were clearly observed in the valence spectra, and no Eu2+ components were observed within experimental accuracy, confirming a robust Eu3+ state. The band structure and Fermi surfaces revealed by the ARPES measurements were compared to band structure calculations based on the density-functional theory for LaPd3 and YPd3. We found that the calculation for LaPd3 provides a better description for our ARPES results. The effective electron masses estimated from the ARPES spectra near the Fermi level are in good agreement with the corresponding cyclotron effective masses in previous de Haas-van Alphen experiments.