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arXiv · 0808.1063

Sheet Dependence on Superconducting Gap in Oxygen-Deficient Iron-based Oxypnictide Superconductors NdFeAs0.85

Yoshihiro Aiura·Koji Sato·Hideaki Iwasawa·Yosuke Nakashima·Akihiro Ino·Masashi Arita·Kenya Shimada·Hirofumi Namatame·Masaki Taniguchi·Izumi Hase·Kiichi Miyazawa·Parasharam M. Shirage·Hiroshi Eisaki·Hijiri Kito·Akira Iyo
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Abstract

Photoemission spectroscopy with low-energy tunable photons on oxygen-deficient iron-based oxypnictide superconductors NdFeAsO0.85 (Tc=52K) reveals a distinct photon-energy dependence of the electronic structure near the Fermi level (EF). A clear shift of the leading-edge can be observed in the superconducting states with 9.5 eV photons, while a clear Fermi cutoff with little leading-edge shift can be observed with 6.0 eV photons. The results are indicative of the superconducting gap opening not on the hole-like ones around Gamma (0,0) point but on the electron-like sheets around M(pi,pi) point.

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Yoshihiro Aiura, Koji Sato, Hideaki Iwasawa, Yosuke Nakashima, Akihiro Ino, Masashi Arita, Kenya Shimada, Hirofumi Namatame, Masaki Taniguchi, Izumi Hase, Kiichi Miyazawa, Parasharam M. Shirage, Hiroshi Eisaki, Hijiri Kito, Akira Iyo. 2008-08-07. Sheet Dependence on Superconducting Gap in Oxygen-Deficient Iron-based Oxypnictide Superconductors NdFeAs0.85. https://doi.org/10.1143/jpsj.77.103712

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