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arXiv · 1307.7016

Switching of intra-orbital spin excitations in electron-doped iron pnictide superconductors

Soshi Iimura·Satoru Matsuishi·Masashi Miyakawa·Takashi Taniguchi·Katsuhiro Suzuki·Hidetomo Usui·Kazuhiko Kuroki·Ryoichi Kajimoto·Mitsutaka Nakamura·Yasuhiro Inamura·Kazuhiko Ikeuchi·Sungdae Ji·Hideo Hosono
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Abstract

We investigate the doping dependence of the magnetic excitations in two-superconducting-dome-system LaFeAsO1-xDx. Using inelastic neutron scattering, spin fluctuations at different wavenumbers were observed under both superconducting domes around x = 0.1 and 0.4, but vanished at x = 0.2 corresponding to the Tc valley. Theoretical calculations indicate that the characteristic doping dependence of spin fluctuations is rationally explained as a consequence of the switching of the two intra-orbital nestings within Fe-3dYZ, ZX and 3dX2-Y2 by electron doping. The present results imply that the multi-orbital nature plays an important role in the doping and / or material dependence of the Tc of the iron pnictide superconductors.

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Soshi Iimura, Satoru Matsuishi, Masashi Miyakawa, Takashi Taniguchi, Katsuhiro Suzuki, Hidetomo Usui, Kazuhiko Kuroki, Ryoichi Kajimoto, Mitsutaka Nakamura, Yasuhiro Inamura, Kazuhiko Ikeuchi, Sungdae Ji, Hideo Hosono. 2013-08-02. Switching of intra-orbital spin excitations in electron-doped iron pnictide superconductors. https://doi.org/10.1103/physrevb.88.060501

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