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arXiv · 0909.2917

Bulk 5f electronic states in uranium monochalcogenide US

Y. Takeda·T. Okane·T. Ohkochi·Y. Saitoh·H. Yamagami·A. Fujimori·A. Ochiai
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Abstract

We have investigated the electronic states of the uranium monochalcogenide US, which is a typical ferromagnetic uranium compound, using soft x-ray photoemission spectroscopy (SX-PES). In early ultraviolet photoemission spectroscopy studies, two peak structures of the U 5f states were observed and have been interpreted that one has an itinerant character around the Fermi level (EF) and the other located below EF has a character of localized U 5f electrons. In this study, the intrinsic bulk valence-band spectrum of US was first deduced by estimating the contribution of surface states to the valence-band spectrum using core-level photoemission spectra. We conclude that the electronic structure of US can be basically described by the itinerant nature of the U 5f electrons from comparison with theoretical valence-band spectra obtained by band-structure calculation in the local-density approximation.

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Y. Takeda, T. Okane, T. Ohkochi, Y. Saitoh, H. Yamagami, A. Fujimori, A. Ochiai. 2009-09-16. Bulk 5f electronic states in uranium monochalcogenide US. https://arxiv.org/abs/0909.2917

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