Electronic structure of UTe₂ studied by photoelectron spectroscopy

The electronic structure of the unconventional superconductor UTe₂ was studied by resonant photoelectron spectroscopy (RPES) and angle-resolved photoelectron spectroscopy (ARPES) with soft X-ray synchrotron radiation. The partial U 5 f density of states of UTe₂ were imaged by the U 4d–5 f RPES and it was found that the U 5 f state has an itinerant character, but there exists an incoherent peak due to the strong electron correlation effects. Furthermore, an anomalous admixture of the U 5 f states into the Te 5 p bands was observed at a higher binding energy, which cannot be explained by band structure calculations. On the other hand, the band structure of UTe₂ was obtained by ARPES and its overall band structure were mostly explained by band structure calculations. These results suggest that the U 5 f states of UTe₂ have itinerant but strongly-correlated nature with enhanced hybridization with the Te 5 p states.