title: Te concentration dependent photoemission and inverse-photoemission study of FeSe1-xTex.
abstract: We have characterized the electronic structure of FeSe1-xTexfor variousxvalues using soft x-ray photoemission spectroscopy (SXPES), high-resolution photoemission spectroscopy (HRPES) and inverse photoemission spectroscopy (IPES). The SXPES valence band spectral shape shows that the 2 eV feature in FeSe, which was ascribed to the lower Hubbard band in previous theoretical studies, becomes less prominent with increasingx. HRPES exhibits systematicxdependence of the structure near the Fermi level (EF): its splitting nearEFand filling of the pseudogap in FeSe. IPES shows two features, nearEFand approximately 6 eV aboveEF; the former may be related to the Fe 3d states hybridized with chalcogenide p states, while the latter may consist of plane-wave-like and Se d components. In the incident electron energy dependence of IPES, the density of states nearEFfor FeSe and FeTe has the Fano lineshape characteristic of resonant behavior. These compounds exhibit different resonance profiles, which may reflect the differences in their electronic structures. By combining the PES and IPES data the on-site Coulomb energy was estimated at 3.5 eV for FeSe.
authors.affiliation: The Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima-naka, Okayama 700-8530, Japan; Japan Science and Technology Agency-Transformative Research Project on Iron Pnictides (JST-TRIP), Tsukuba, Ibaraki 305-0047, Japan; Core Research for Evolutional Science and Technology (CREST) Japan Science and Technology Agency, Okayama 700-8530, Japan; Research Laboratory for Surface Science, Okayama University, 3-1-1 Tsushima-naka, Okayama 700-8530, Japan.
authors.forename: Takayoshi
authors.initials: T
authors.lastname: Yokoya
authors.affiliation: The Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima-naka, Okayama 700-8530, Japan.
authors.forename: Rikiya
authors.initials: R
authors.lastname: Yoshida
authors.affiliation: Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8526, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Utsumi
authors.affiliation: The Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima-naka, Okayama 700-8530, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Tsubota
authors.affiliation: The Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima-naka, Okayama 700-8530, Japan; Core Research for Evolutional Science and Technology (CREST) Japan Science and Technology Agency, Okayama 700-8530, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Okazaki
authors.affiliation: The Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima-naka, Okayama 700-8530, Japan; Japan Science and Technology Agency-Transformative Research Project on Iron Pnictides (JST-TRIP), Tsukuba, Ibaraki 305-0047, Japan; Core Research for Evolutional Science and Technology (CREST) Japan Science and Technology Agency, Okayama 700-8530, Japan; Research Laboratory for Surface Science, Okayama University, 3-1-1 Tsushima-naka, Okayama 700-8530, Japan.
authors.forename: Takanori
authors.initials: T
authors.lastname: Wakita
authors.affiliation: Japan Science and Technology Agency-Transformative Research Project on Iron Pnictides (JST-TRIP), Tsukuba, Ibaraki 305-0047, Japan; National Institute for Materials Science, Tsukuba, Ibaraki 305-0047, Japan; University of TsukubaGraduate School of Pure and Applied Sciences, Tsukuba, Ibaraki 305-8577, Japan.
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Mizuguchi
authors.affiliation: Japan Science and Technology Agency-Transformative Research Project on Iron Pnictides (JST-TRIP), Tsukuba, Ibaraki 305-0047, Japan; National Institute for Materials Science, Tsukuba, Ibaraki 305-0047, Japan; University of TsukubaGraduate School of Pure and Applied Sciences, Tsukuba, Ibaraki 305-8577, Japan.
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Takano
authors.affiliation: Japan Synchrotron Radiation Research Institute, Sayo, Hyogo 679-5198, Japan.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Muro
authors.affiliation: Japan Synchrotron Radiation Research Institute, Sayo, Hyogo 679-5198, Japan.
authors.forename: Yukako
authors.initials: Y
authors.lastname: Kato
authors.affiliation: Core Research for Evolutional Science and Technology (CREST) Japan Science and Technology Agency, Okayama 700-8530, Japan; Department of Applied Chemistry, The University of Tokyo, Bunkyo-ku, Tokyo 113-8656, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kumigashira
authors.affiliation: Core Research for Evolutional Science and Technology (CREST) Japan Science and Technology Agency, Okayama 700-8530, Japan; Department of Applied Chemistry, The University of Tokyo, Bunkyo-ku, Tokyo 113-8656, Japan.
authors.forename: Masaharu
authors.initials: M
authors.lastname: Oshima
authors.affiliation: Japan Science and Technology Agency-Transformative Research Project on Iron Pnictides (JST-TRIP), Tsukuba, Ibaraki 305-0047, Japan; Department of Physics, Graduate School of Science, Kobe University, Kobe, Hyogo 657-8501, Japan.
authors.forename: Hisatomo
authors.initials: H
authors.lastname: Harima
authors.affiliation: Japan Science and Technology Agency-Transformative Research Project on Iron Pnictides (JST-TRIP), Tsukuba, Ibaraki 305-0047, Japan; National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki 305-8568, Japan.
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Aiura
authors.affiliation: Japan Science and Technology Agency-Transformative Research Project on Iron Pnictides (JST-TRIP), Tsukuba, Ibaraki 305-0047, Japan; Hiroshima Synchrotron Radiation Center, Hiroshima University, Higashihiroshima, Hiroshima 739-0046, Japan.
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Sato
authors.affiliation: Japan Science and Technology Agency-Transformative Research Project on Iron Pnictides (JST-TRIP), Tsukuba, Ibaraki 305-0047, Japan; Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8526, Japan.
authors.forename: Akihiro
authors.initials: A
authors.lastname: Ino
authors.affiliation: Hiroshima Synchrotron Radiation Center, Hiroshima University, Higashihiroshima, Hiroshima 739-0046, Japan.
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Namatame
authors.affiliation: Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8526, Japan; Hiroshima Synchrotron Radiation Center, Hiroshima University, Higashihiroshima, Hiroshima 739-0046, Japan.
authors.forename: Masaki
authors.initials: M
authors.lastname: Taniguchi
authors.affiliation: The Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima-naka, Okayama 700-8530, Japan; Japan Science and Technology Agency-Transformative Research Project on Iron Pnictides (JST-TRIP), Tsukuba, Ibaraki 305-0047, Japan; Core Research for Evolutional Science and Technology (CREST) Japan Science and Technology Agency, Okayama 700-8530, Japan; Research Laboratory for Surface Science, Okayama University, 3-1-1 Tsushima-naka, Okayama 700-8530, Japan.
authors.forename: Masaaki
authors.initials: M
authors.lastname: Hirai
authors.affiliation: The Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima-naka, Okayama 700-8530, Japan; Japan Science and Technology Agency-Transformative Research Project on Iron Pnictides (JST-TRIP), Tsukuba, Ibaraki 305-0047, Japan; Core Research for Evolutional Science and Technology (CREST) Japan Science and Technology Agency, Okayama 700-8530, Japan; Research Laboratory for Surface Science, Okayama University, 3-1-1 Tsushima-naka, Okayama 700-8530, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Muraoka
keywords: FeSe(1−x)Tex; electronic structure; high-resolution photoemission spectroscopy; inverse photoemission spectroscopy; soft x-ray photoemission spectroscopy