Superconducting Gap and Pseudogap in Sm(O$_{1-x}$F$_x$)FeAs Layered Superconductor from Photoemission Spectroscopy

Haiyun Liu; Xiaowen Jia; Wentao Zhang; Lin Zhao; Jianqiao Meng; Guodong Liu; Xiaoli Dong; G. Wu; R. H. Liu; X. H. Chen; Z. A. Ren; Wei Yi; G. C. Che; G. F. Chen; N. L. Wang; Guiling Wang; Yong Zhou; Yong Zhu; Xiaoyang Wang; Zhongxian Zhao; Zuyan Xu; Chuangtian Chen; X. J. Zhou

arXiv · 0805.3821

Superconducting Gap and Pseudogap in Sm(O$_{1-x}$F$_x$)FeAs Layered Superconductor from Photoemission Spectroscopy

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Abstract

High resolution photoemission measurements have been carried out on non-superconducting SmOFeAs parent compound and superconducting Sm(O$_{1-x}$F$_x$)FeAs (x=0.12, and 0.15) compounds. The momentum-integrated spectra exhibit a clear Fermi cutoff that shows little leading-edge shift in the superconducting state which suggests the Fermi surface sheet(s) around the $Γ$ point may not be gapped in this multiband superconductors. A robust feature at 13 meV is identified in all these samples. Spectral weight suppression near E$_F$ with decreasing temperature is observed in both undoped and doped samples that points to a possible existence of a pseudogap in these Fe-based compounds.

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Haiyun Liu, Xiaowen Jia, Wentao Zhang, Lin Zhao, Jianqiao Meng, Guodong Liu, Xiaoli Dong, G. Wu, R. H. Liu, X. H. Chen, Z. A. Ren, Wei Yi, G. C. Che, G. F. Chen, N. L. Wang, Guiling Wang, Yong Zhou, Yong Zhu, Xiaoyang Wang, Zhongxian Zhao, Zuyan Xu, Chuangtian Chen, X. J. Zhou. 2008-05-26. Superconducting Gap and Pseudogap in Sm(O$_{1-x}$F$_x$)FeAs Layered Superconductor from Photoemission Spectroscopy. https://arxiv.org/abs/0805.3821

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