2019/11/11 by H. Suzuki, T. Kobayashi, S. Miyasaka +14
Materials Science · Physics and Astronomy · #Angle-resolved photoemission spectroscopy #Band gap #Electron #Fermi level #Fermi surface #Iron-based superconductors research #Isotropy #Photoemission spectroscopy #Physics of Superconductivity and Magnetism #Superconductivity #Superconductivity in MgB2 and Alloys #Synchrotron radiation #cond-mat.supr-con
paper · pdf · doi:10.1038/s41598-019-52887-y
published as Sci. Rep. 9, 16418 (2019) · This is a pre-print of an article published in Scientific Reports. The final authenticated version is available online at: https://doi.org/10.1038/s41598-019-52887-y
arxiv created 2019/11/11 · openalex publication_date 2019/11/11 · openalex created_date 2019/11/22 · arxiv updated 2020/06/12 · openalex updated_date 2026/08/06
Abstract The isovalent-substituted iron pnictide compound SrFe 2 (As 1− x P x ) 2 exhibits multiple evidence for nodal superconductivity via various experimental probes, such as the penetration depth, nuclear magnetic resonance and specific heat measurements. The direct identification of the nodal superconducting (SC) gap structure is challenging, partly because the presence of nodes is not protected by symmetry but instead caused by an accidental sign change of the order parameter, and also because of the three-dimensionality of the electronic structure. We have studied the SC gaps of SrFe 2 (As 0.65 P 0.35 ) 2 in three-dimensional momentum space by synchrotron and laser-based angle-resolved photoemission spectroscopy. The three hole Fermi surfaces (FSs) at the zone center have SC gaps with different magnitudes, whereas the SC gaps of the electron FSs at the zone corner are almost isotropic and k z -independent. As a possible nodal SC gap structure, we propose that the SC gap of the outer hole FS changes sign around the Z-X [(0, 0, 2 π ) − ( π , π , 2 π )] direction.