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arXiv · 0806.3860

Electronic Structure and Electron Correlation in LaFeAsO_{1-x}F_x and LaFePO_{1-x}F_x

Walid Malaeb·Teppei Yoshida·Takashi Kataoka·Atsushi Fujimori·Masato Kubota·Kanta Ono·Hidetomo Usui·Kazuhiko Kuroki·Ryotaro Arita·Hideo Aoki·Yoichi Kamihara·Masahiro Hirano·Hideo Hosono
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Abstract

Photoemission spectroscopy is used to investigate the electronic structure of the newly discovered iron-based superconductors LaFeAsO_{1-x}F_x and LaFePO_{1-x}F_x. Line shapes of the Fe 2p core-level spectra suggest an itinerant character of Fe 3d electrons. The valence-band spectra are generally consistent with band-structure calculations except for the shifts of Fe 3d-derived peaks toward the Fermi level. From spectra taken in the Fe 3p -> 3d core-absorption region, we have obtained the experimental Fe 3d partial density of states, and explained it in terms of a band-structure calculation with a phenomenological self-energy correction, yielding a mass renormalization factor of ~< 2.

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Walid Malaeb, Teppei Yoshida, Takashi Kataoka, Atsushi Fujimori, Masato Kubota, Kanta Ono, Hidetomo Usui, Kazuhiko Kuroki, Ryotaro Arita, Hideo Aoki, Yoichi Kamihara, Masahiro Hirano, Hideo Hosono. 2008-06-24. Electronic Structure and Electron Correlation in LaFeAsO_{1-x}F_x and LaFePO_{1-x}F_x. https://doi.org/10.1143/jpsj.77.093714

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