Possible nodal superconducting gap emerging at the Lifshitz transition in heavily hole-doped Ba0.1K0.9Fe2As2

N. Xu; P. Richard; X. Shi; A. van Roekeghem; T. Qian; E. Razzoli; E. Rienks; G. -F. Chen; E. Ieki; K. Nakayama; T. Sato; T. Takahashi; M. Shi; H. Ding

doi:10.1103/physrevb.88.220508

arXiv · 1308.3888

Possible nodal superconducting gap emerging at the Lifshitz transition in heavily hole-doped Ba0.1K0.9Fe2As2

N. Xu·P. Richard·X. Shi·A. van Roekeghem·T. Qian·E. Razzoli·E. Rienks·G. -F. Chen·E. Ieki·K. Nakayama·T. Sato·T. Takahashi·M. Shi·H. Ding

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Abstract

We performed a high energy resolution ARPES investigation of over-doped Ba0.1K0.9Fe2As2 with T_c= 9 K. The Fermi surface topology of this material is similar to that of KFe2As2 and differs from that of slightly less doped Ba0.3K0.7Fe2As2, implying that a Lifshitz transition occurred between x=0.7 and x=0.9. Albeit for a vertical node found at the tip of the emerging off-M-centered Fermi surface pocket lobes, the superconducting gap structure is similar to that of Ba0.3K0.7Fe2As2, suggesting that the paring interaction is not driven by the Fermi surface topology.

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N. Xu, P. Richard, X. Shi, A. van Roekeghem, T. Qian, E. Razzoli, E. Rienks, G. -F. Chen, E. Ieki, K. Nakayama, T. Sato, T. Takahashi, M. Shi, H. Ding. 2013-08-18. Possible nodal superconducting gap emerging at the Lifshitz transition in heavily hole-doped Ba0.1K0.9Fe2As2. https://doi.org/10.1103/physrevb.88.220508

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