Unusual Pseudogap-like Features Observed in Iron Oxypnictide Superconductors

Abstract

We have performed a temperature-dependent angle-integrated laser photoemission study of iron oxypnictide superconductors LaFeAsO:F and LaFePO:F exhibiting critical transition temperatures (Tc's) of 26 K and 5 K, respectively. We find that high-Tc LaFeAsO:F exhibits a temperature-dependent pseudogap-like feature extending over ~0.1 eV about the Fermi level at 250 K, whereas such a feature is absent in low-Tc LaFePO:F. We also find ~20-meV pseudogap-like features and signatures of superconducting gaps both in LaFeAsO:F and LaFePO:F. We discuss the possible origins of the unusual pseudogap-like features through comparison with the high-Tc cuprates.

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Cited by in corpus (4)

• Pseudogap from ARPES experiment: three gaps in cuprates and topological superconductivity
• Pseudogap formation above the superconducting dome in iron-pnictides
• Electronic Structure of Superconducting FeSe Studied by High-Resolution Photoemission Spectroscopy
• High-Temperature Majorana Fermions in Magnet-Superconductor Hybrid Systems