Electronic Structure of Prototype AFe_2As_2 and ReOFeAs High-Temperature Superconductors: a Comparison

I. A. Nekrasov; Z. V. Pchelkina; M. V. Sadovskii

doi:10.1134/s0021364008140166

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arXiv · 0806.2630

Electronic Structure of Prototype AFe_2As_2 and ReOFeAs High-Temperature Superconductors: a Comparison

I. A. Nekrasov·Z. V. Pchelkina·M. V. Sadovskii

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Abstract

We have performed ab initio LDA calculations of electronic structure of newly discovered prototype high-temperature superconductors AFe_2As_2 (A=Ba,Sr) and compared it with previously calculated electronic spectra of ReOFeAs (Re=La,Ce,Pr,Nd,Sm). In all cases we obtain almost identical densities of states in rather wide energy interval (up to 1 eV) around the Fermi level. Energy dispersions are also very similar and almost two-dimensional in this energy interval, leading to the same basic (minimal) model of electronic spectra, determined mainly by Fe d-orbitals of FeAs layers. The other constituents, such as A ions or rare earths Re (or oxygen states) are more or less irrelevant for superconductivity. LDA Fermi surfaces for AFe_2As_2 are also very similar to that of ReOFeAs. This makes the more simple AFe_2As_2 a generic system to study high-temperature superconductivity in FeAs - layered compounds.

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I. A. Nekrasov, Z. V. Pchelkina, M. V. Sadovskii. 2008-06-16. Electronic Structure of Prototype AFe_2As_2 and ReOFeAs High-Temperature Superconductors: a Comparison. https://doi.org/10.1134/s0021364008140166

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