Electronic structure of CaFe2As2: Contribution of itinerant Fe 3d-states to the Fermi Level

E. Z. Kurmaev; J. A. McLeod; A. Buling; N. A. Skorikov; A. Moewes; M. Neumann; M. A. Korotin; Yu. A. Izyumov; N. Ni; P. C. Canfield

doi:10.1103/physrevb.80.054508

arXiv · 0902.1141

Electronic structure of CaFe2As2: Contribution of itinerant Fe 3d-states to the Fermi Level

E. Z. Kurmaev·J. A. McLeod·A. Buling·N. A. Skorikov·A. Moewes·M. Neumann·M. A. Korotin·Yu. A. Izyumov·N. Ni·P. C. Canfield

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Abstract

We present density functional theory (DFT) calculations and a full set of X-ray spectra (resonant inelastic X-ray scattering and X-ray photoelectron spectra) measurements of single crystal CaFe2As2. The experimental valence band spectra are consistent with our DFT calculations. Both theory and experiment show that the Fe 3d-states dominate the Fermi level and hybridize with Ca 3d-states. The simple shape of Xray photoelectron (XPS) Fe 2p-core level spectrum (without any satellite structure typical for correlated systems) suggests itinerant character of the Fe 3d-electrons. Based on the similarity of the calculated and experimental Fe 3d-states distribution in LaOFeAs and CaFe2As2 we conclude that superconductivity in the FeAs-systems can be described within a minimal model, taking into account only Fe 3d-bands close to the Fermi level.

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E. Z. Kurmaev, J. A. McLeod, A. Buling, N. A. Skorikov, A. Moewes, M. Neumann, M. A. Korotin, Yu. A. Izyumov, N. Ni, P. C. Canfield. 2009-02-06. Electronic structure of CaFe2As2: Contribution of itinerant Fe 3d-states to the Fermi Level. https://doi.org/10.1103/physrevb.80.054508

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