Abstract
The electronic structure in the normal state of oxypnictide superconductors has been investigated with x-ray absorption and photoemission spectroscopy. All of the data exhibit signatures of Fe -electron itinerancy. Exchange multiplets appearing in the Fe core level indicate the presence of itinerant spin fluctuations. These findings suggest that the underlying physics and the origin of superconductivity in these materials are likely to be quite different from those of the cuprate high-temperature superconductors. These materials provide opportunities for elucidating the role of magnetic fluctuations in high-temperature superconductivity.
- Received 27 July 2008
DOI:https://doi.org/10.1103/PhysRevLett.101.267001
©2008 American Physical Society