Photoemission and muon spin relaxation spectroscopy of the iron-based Rb0.77Fe1.61Se2 superconductor: Crucial role of the cigar-shaped Fermi surface
J. Maletz , B. Zabolotnyy , V. Evtushinsky , N. Yaresko , A. Kordyuk , Z. Shermadini , H. Luetkens , K. Sedlak , R. Khasanov , A. Amato , Anna Krztoń-Maziopa , K. Conder , E. Pomjakushina , H. Klauss , L. Rienks , B. Büchner , S. V. Borisenko
AbstractIn this study, we investigate the electronic and magnetic properties of Rb0.77Fe1.61Se2 (Tc = 32.6 K) in normal and superconducting states by means of photoemission and μSR spectroscopies as well as band-structure calculations.We demonstrate that the unusual behavior of these materials is the result of separation into metallic (∼12%) and insulating (∼88%) phases. Only the former becomes superconducting and has a usual electronic structure of electron-doped FeSe slabs. Our results thus imply that the antiferromagnetic insulating phase is just a by-product of Rb intercalation and its magnetic properties have no direct relation to the superconductivity. Instead, we find that also in this class of iron-based compounds, the key ingredient for superconductivity is a certain proximity of a Van Hove singularity to the Fermi level.
|Journal series||Physical Review B, ISSN 1098-0121|
|Publication size in sheets||0.5|
|Keywords in English||intercalated, iron chalcogenide superconductor, Fermi surface, ARPES, superconductivity|
|Score|| = 35.0, 23-01-2020, ArticleFromJournal|
= 35.0, 23-01-2020, ArticleFromJournal
|Publication indicators||= 20; = 15; : 2013 = 1.326; : 2013 = 3.664 (2) - 2013=3.564 (5)|
|Citation count*||9 (2015-11-27)|
* presented citation count is obtained through Internet information analysis and it is close to the number calculated by the Publish or Perish system.