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arXiv · 1211.4679

Itinerant Nature of U 5f States in Uranium Mononitride UN Revealed by Angle Resolved Photoelectron Spectroscopy

Shin-ichi Fujimori·Takuo Ohkochi·Tetsuo Okane·Yuji Saitoh·Atsushi Fujimori·Hiroshi Yamagami·Yoshinori Haga·Etsuji Yamamoto·Yoshichika Onuki
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Abstract

The electronic structure of the antiferromagnet uranium nitride (UN) has been studied by angle resolved photoelectron spectroscopy using soft X-rays (hn=420-520 eV). Strongly dispersive bands with large contributions from the U 5f states were observed in ARPES spectra, and form Fermi surfaces. The band structure as well as the Fermi surfaces in the paramagnetic phase are well explained by the band-structure calculation treating all the U 5f electrons as being itinerant, suggesting that itinerant description of the U 5f states is appropriate for this compound. On the other hand, changes in the spectral function due to the antiferromagnetic transition were very small. The shapes of the Fermi surfaces in a paramagnetic phase are highly three-dimensional, and the nesting of Fermi surfaces is unlikely as the origin of the magnetic ordering.

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Shin-ichi Fujimori, Takuo Ohkochi, Tetsuo Okane, Yuji Saitoh, Atsushi Fujimori, Hiroshi Yamagami, Yoshinori Haga, Etsuji Yamamoto, Yoshichika Onuki. 2012-11-20. Itinerant Nature of U 5f States in Uranium Mononitride UN Revealed by Angle Resolved Photoelectron Spectroscopy. https://doi.org/10.1103/physrevb.86.235108

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