Core-Level Photoelectron Spectroscopy Study of UTe$_2$

TL;DR

This study uses core-level photoelectron spectroscopy to analyze the valence state of uranium in UTe₂, revealing a mixed-valence state with itinerant 5f³ characteristics.

Contribution

It provides new insights into the electronic state of UTe₂, showing mixed valence and itinerant 5f³ behavior through spectroscopic analysis.

Findings

UTe₂ has a U 4f core-level spectrum similar to UB₂

Broader main peak and satellite structures indicate mixed valence

U 5f state predominantly exhibits itinerant 5f³ configuration

Abstract

The valence state of UTe$_2$ was studied by core-level photoelectron spectroscopy. The main peak position of the U $4f$ core-level spectrum of UTe$_2$ coincides with that of UB$_2$, which is an itinerant compound with a nearly $5f^3$ configuration. However, the main peak of UTe$_2$ is broader than that of UB$_2$, and satellite structures are observed in the higher binding energy side of the main peak, which are characteristics of mixed-valence uranium compounds. These results suggest that the U 5$f$ state in UTe$_2$ is in a mixed valence state with a dominant contribution from the itinerant $5f^3$ configuration.