Electronic structure of heavily electron-doped BaFe$_{1.7}$Co$_{0.3}$As$_2$ studied by angle-resolved photoemission

Y. Sekiba; T. Sato; K. Nakayama; K. Terashima; P. Richard; J. H. Bowen; H. Ding; Y. -M. Xu; L. J. Li; G. H. Cao; Z. -A. Xu; T. Takahashi

doi:10.1088/1367-2630/11/2/025020

arXiv · 0812.4111

Electronic structure of heavily electron-doped BaFe$_{1.7}$Co$_{0.3}$As$_2$ studied by angle-resolved photoemission

Y. Sekiba·T. Sato·K. Nakayama·K. Terashima·P. Richard·J. H. Bowen·H. Ding·Y. -M. Xu·L. J. Li·G. H. Cao·Z. -A. Xu·T. Takahashi

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Abstract

We have performed high-resolution angle-resolved photoemission spectroscopy on heavily electron-doped non-superconducting (SC) BaFe$_{1.7}$Co$_{0.3}$As$_2$. We find that the two hole Fermi surface pockets at the zone center observed in the hole-doped superconducting Ba$_{0.6}$K$_{0.4}$Fe$_2$As$_2$ are absent or very small in this compound, while the two electron pockets at the M point significantly expand due to electron doping by the Co substitution. Comparison of the Fermi surface between non-SC and SC samples indicates that the coexistence of hole and electron pockets connected via the antiferromagnetic wave vector is essential in realizing the mechanism of superconductivity in the iron-based superconductors.

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Y. Sekiba, T. Sato, K. Nakayama, K. Terashima, P. Richard, J. H. Bowen, H. Ding, Y. -M. Xu, L. J. Li, G. H. Cao, Z. -A. Xu, T. Takahashi. 2009-03-05. Electronic structure of heavily electron-doped BaFe$_{1.7}$Co$_{0.3}$As$_2$ studied by angle-resolved photoemission. https://doi.org/10.1088/1367-2630%2F11%2F2%2F025020

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