Electronic structure of ThRu2Si2 studied by angle-resolved photoelectron spectroscopy: Elucidating the contribution of U 5f states in URu2Si2

TL;DR

This study uses ARPES to analyze the electronic structure of ThRu2Si2 and compares it with URu2Si2, revealing significant hybridization of U 5f states in the latter, which is crucial for understanding its electronic properties.

Contribution

It provides detailed experimental band structures and Fermi surface shapes of ThRu2Si2 and compares them with URu2Si2 to elucidate the role of U 5f electrons.

Findings

ThRu2Si2's band structure matches DFT calculations.

URu2Si2 shows different spectral features indicating U 5f hybridization.

U 5f electrons in URu2Si2 are strongly hybridized and itinerant.

Abstract

The electronic structure of ThRu2Si2 was studied by angle-resolved photoelectron spectroscopy (ARPES) with incident photon energies of hn=655-745 eV. Detailed band structure and the three-dimensional shapes of Fermi surfaces were derived experimentally, and their characteristic features were mostly explained by means of band structure calculations based on the density functional theory. Comparison of the experimental ARPES spectra of ThRu2Si2 with those of URu2Si2 shows that they have considerably different spectral profiles particularly in the energy range of 1 eV from the Fermi level, suggesting that U 5f states are substantially hybridized in these bands. The relationship between the ARPES spectra of URu2Si2 and ThRu2Si2 is very different from the one between the ARPES spectra of CeRu2Si2 and LaRu2Si2, where the intrinsic difference in their spectra is limited only in the very vicinity of the Fermi energy. The present result suggests that the U 5f electrons in URu2Si2 have strong hybridization with ligand states and have an essentially itinerant character.