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arXiv · 0805.2647

Unusual Pseudogap-like Features Observed in Iron Oxypnictide Superconductors

Y. Ishida·T. Shimojima·K. Ishizaka·T. Kiss·M. Okawa·T. Togashi·S. Watanabe·X. -Y. Wang·C. -T. Chen·Y. Kamihara·M. Hirano·H. Hosono·S. Shin
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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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Y. Ishida, T. Shimojima, K. Ishizaka, T. Kiss, M. Okawa, T. Togashi, S. Watanabe, X. -Y. Wang, C. -T. Chen, Y. Kamihara, M. Hirano, H. Hosono, S. Shin. 2009-01-15. Unusual Pseudogap-like Features Observed in Iron Oxypnictide Superconductors. https://doi.org/10.1143/jpsjs.77sc.61

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