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arXiv · 1206.2985

Doping-Dependent and Orbital-Dependent Band Renormalization in Ba(Fe_1-xCo_x)_2As_2 Superconductors

T. Sudayama·Y. Wakisaka·T. Mizokawa·S. Ibuka·R. Morinaga·T. J. Sato·M. Arita·H. Namatame·M. Taniguchi·N. L. Saini
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Abstract

Angle resolved photoemission spectroscopy of Ba(Fe1-xCox)2As2 (x = 0.06, 0.14, and 0.24) shows that the width of the Fe 3d yz/zx hole band depends on the doping level. In contrast, the Fe 3d x^2-y^2 and 3z^2-r^2 bands are rigid and shifted by the Co doping. The Fe 3d yz/zx hole band is flattened at the optimal doping level x = 0.06, indicating that the band renormalization of the Fe 3d yz/zx band correlates with the enhancement of the superconducting transition temperature. The orbital-dependent and doping-dependent band renormalization indicates that the fluctuations responsible for the superconductivity is deeply related to the Fe 3d orbital degeneracy.

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T. Sudayama, Y. Wakisaka, T. Mizokawa, S. Ibuka, R. Morinaga, T. J. Sato, M. Arita, H. Namatame, M. Taniguchi, N. L. Saini. 2012-06-14. Doping-Dependent and Orbital-Dependent Band Renormalization in Ba(Fe_1-xCo_x)_2As_2 Superconductors. https://doi.org/10.1143/jpsj.80.113707

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