2014/10/31 by Daniel Guterding, Harald O. Jeschke, P. J. Hirschfeld +2 · 62 citations
Chemistry · Materials Science · Physics and Astronomy · #Ab initio #Alkali metal #Chemistry #Condensed matter physics #Crystallography #Doping #Electronic structure #Inorganic Chemistry and Materials #Iron-based superconductors research #Lithium (medication) #Materials science #Pairing #Physics #Quantum mechanics #Rare-earth and actinide compounds #Superconductivity #cond-mat.str-el #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevb.91.041112
published in Physical Review B 91(4) (American Physical Society)
arxiv created 2015/01/09 · openalex publication_date 2015/01/15 · arxiv updated 2015/01/16 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
In the recently synthesized Lix(NH2)y(NH3)zFe2Se2 family of iron chalcogenides, a molecular spacer consisting of lithium ions, lithium amide, and ammonia separates the layers of FeSe. It has been shown that upon variation of the chemical composition of the spacer layer, superconducting transition temperatures can reach Tc\ensuremath∼44\phantom\rule0.28em0exK, but the relative importance of the layer separation and effective doping to the Tc enhancement is currently unclear. Using state of the art band structure unfolding techniques, we construct eight-orbital models from ab initio density functional theory calculations for these materials. Within an RPA spin-fluctuation approach, we show that the electron doping enhances the superconducting pairing, which is of s_\ifmmode±\else\textpm\fi symmetry and explain the experimentally observed limit to Tc in the molecular spacer intercalated FeSe class of materials.