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arXiv · 1002.0769

Orbital Symmetry of Ba(Fe1-xCox)2As2 Superconductors Probed with X-ray Absorption Spectroscopy

C. Parks Cheney·F. Bondino·T. A. Callcott·P. Vilmercati·D. Ederer·E. Magnano·M. Malvestuto·F. Parmigiani·A. S. Sefat·M. A. McGuire·R. Jin·B. C. Sales·D. Mandrus·D. J. Singh·J. W. Freeland·N. Mannella
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Abstract

The orbital symmetries of electron doped iron-arsenide superconductors Ba(Fe1-xCox)2As2 have been measured with x-ray absorption spectroscopy. The data reveal signatures of Fe d electron itinerancy, weak electronic correlations, and a high degree of Fe-As hybridization related to the bonding topology of the Fe dxz+yz states, which are found to contribute substantially at the Fermi level. The energies and detailed orbital character of Fe and As derived unoccupied s and d states are found to be in remarkably good agreement with the predictions of standard density functional theory.

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C. Parks Cheney, F. Bondino, T. A. Callcott, P. Vilmercati, D. Ederer, E. Magnano, M. Malvestuto, F. Parmigiani, A. S. Sefat, M. A. McGuire, R. Jin, B. C. Sales, D. Mandrus, D. J. Singh, J. W. Freeland, N. Mannella. 2010-04-05. Orbital Symmetry of Ba(Fe1-xCox)2As2 Superconductors Probed with X-ray Absorption Spectroscopy. https://doi.org/10.1103/physrevb.81.104518

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