Evidence for Quasilocalized5fElectronic States inUSbxTe1−x

Abstract

We have studied the "$5f$, $6d$" electron states of the system $\mathrm{U}{\mathrm{Sb}}_x{\mathrm{Te}}_{1-x}$ (100) using photoemission spectroscopy with synchrotron radiation. In contrast with the generally accepted picture of uranium chalcogenides and pnictides, we find for UTe that the main $5f$ level lies 0.75 eV below $E_{\mathrm{F}}$ rather than at $E_{\mathrm{F}}$ and that $6d$ states exist at $E_{\mathrm{F}}$. Our results may be explained with a model having a correlated quasilocalized $5f^{3-\delta }(\delta =0-0.5\mathrm{}$) level resonant with broader $6d$ bands rather than bandlike $5f$ levels.