Band Structure and Fermi Surface of an Extremely Overdoped Iron-Based Superconductor KFe2As2

T. Sato; K. Nakayama; Y. Sekiba; P. Richard; Y. -M. Xu; S. Souma; T. Takahashi; G. F. Chen; J. L. Luo; N. L. Wang; H. Ding

doi:10.1103/physrevlett.103.047002

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arXiv · 0810.3047

Band Structure and Fermi Surface of an Extremely Overdoped Iron-Based Superconductor KFe2As2

T. Sato·K. Nakayama·Y. Sekiba·P. Richard·Y. -M. Xu·S. Souma·T. Takahashi·G. F. Chen·J. L. Luo·N. L. Wang·H. Ding

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Abstract

We have performed high-resolution angle-resolved photoemission spectroscopy on heavily overdoped KFe_2As_2 (transition temperature (Tc = 3 K). We observed several renormalized bands near the Fermi level with a renormalization factor of 2-4. While the Fermi surface (FS) around the Brillouin-zone center is qualitatively similar to that of optimally-doped Ba_{1-x}K_xFe_2As_2 (x = 0.4; Tc = 37 K), the FS topology around the zone corner (M point) is markedly different: the two electron FS pockets are completely absent due to excess of hole doping. This result indicates that the electronic states around the M point play an important role in the high-Tc superconductivity of Ba$_{1-x}$K$_x$Fe$_2$As$_2$ and suggests that the interband scattering via the antiferromagnetic wave vector essentially controls the Tc value in the overdoped region.

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T. Sato, K. Nakayama, Y. Sekiba, P. Richard, Y. -M. Xu, S. Souma, T. Takahashi, G. F. Chen, J. L. Luo, N. L. Wang, H. Ding. 2008-10-17. Band Structure and Fermi Surface of an Extremely Overdoped Iron-Based Superconductor KFe2As2. https://doi.org/10.1103/physrevlett.103.047002

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