Abstract:
The electronic spectra of new iron-based high-temperature superconductors and a number of other chemically similar compounds have been discussed and compared with the focus on iron chalcogenide K1−x1−xFe2−y2−ySe22 and isostructural pnictide BaFe22As22 (122). It has been shown that the Fermi surfaces in K1−x1−xFe2−y2−ySe22 are significantly different from those in pnictides. The LDA + DMFT and LDA’ + DMFT calculations have demonstrated that the effect of electron correlations in K1−x1−xFe2−y2−ySe22 on the electronic structure is much stronger than that in the most studied 122 system. The electronic structure of several multiband superconductors similar in chemical composition to iron-based high-temperature superconductors, but having a relatively low TcTc value (such as SrPt22As22, APt33P (A = Sr, Ca, La), and (Sr, Ca)Pd22As22), and the non-superconducting compound BaFe22Se33 has also been discussed. It has been shown that the electronic structure of these systems is significantly different from previously studied iron pnictides and chalcogenides. The TcTc value in these systems can be understood within the simple Bardeen–Cooper–Schrieffer model.
Citation:
I. A. Nekrasov, M. V. Sadovskii, “Electronic structure of new iron-based superconductors: From pnictides to chalcogenides and other similar systems”, Pis'ma v Zh. Èksper. Teoret. Fiz., 99:10 (2014), 687–703; JETP Letters, 99:10 (2014), 598–612