Unusual Electronic Structure and Observation of Dispersion Kink in CeFeAsO Parent Compound of FeAs-Based Superconductors

Haiyun Liu; G. F. Chen; Wentao Zhang; Lin Zhao; Guodong Liu; T. -L. Xia; Xiaowen Jia; Daixiang Mu; Shanyu Liu; Shaolong He; Yingying Peng; Junfeng He; Zhaoyu Chen; Xiaoli Dong; Jun Zhang; Guiling Wang; Yong Zhu; Zuyan Xu; Chuangtian Chen; X. J. Zhou

doi:10.1103/physrevlett.105.027001

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arXiv · 0912.2838

Unusual Electronic Structure and Observation of Dispersion Kink in CeFeAsO Parent Compound of FeAs-Based Superconductors

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Abstract

We report the first comprehensive high-resolution angle-resolved photoemission measurements on CeFeAsO, a parent compound of FeAs-based high temperature superconductors with a mangetic/structural transition at $\sim$150 K. In the magnetic ordering state, four hole-like Fermi surface sheets are observed near $Γ$(0,0) and the Fermi surface near M(+/-$π$,+/-$π$) shows a tiny electron-like pocket at M surrounded by four Dirac cone-like strong spots. The unusual Fermi surface topology deviates strongly from the band structure calculations. The electronic signature of the magnetic/structural transition shows up in the dramatic change of the quasiparticle scattering rate. A dispersion kink at $\sim$ 25meV is for the first time observed in the parent compound of Fe-based superconductors.

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Haiyun Liu, G. F. Chen, Wentao Zhang, Lin Zhao, Guodong Liu, T. -L. Xia, Xiaowen Jia, Daixiang Mu, Shanyu Liu, Shaolong He, Yingying Peng, Junfeng He, Zhaoyu Chen, Xiaoli Dong, Jun Zhang, Guiling Wang, Yong Zhu, Zuyan Xu, Chuangtian Chen, X. J. Zhou. 2010-06-09. Unusual Electronic Structure and Observation of Dispersion Kink in CeFeAsO Parent Compound of FeAs-Based Superconductors. https://doi.org/10.1103/physrevlett.105.027001

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