Two-dome structure in electron-doped iron arsenide superconductors

Soshi Iimura, Satoru Matuishi, Hikaru Sato, Taku Hanna, Yoshinori Muraba, Sung Wng Kim, Jung Eun Kim, Masaki Takata, Hideo Hosono

Research output: Contribution to journalArticle

139 Citations (Scopus)

Abstract

Iron arsenide superconductors based on the material LaFeAsO 1-x F x are characterized by a two-dimensional Fermi surface (FS) consisting of hole and electron pockets yielding structural and antiferromagnetic transitions at x=0. Electron doping by substituting O 2- with F - suppresses these transitions and gives rise to superconductivity with a maximum T c of 26 K at x=0.1. However, the over-doped region cannot be accessed due to the poor solubility of F - above x=0.2. Here we overcome this problem by doping LaFeAsO with hydrogen. We report the phase diagram of LaFeAsO 1-x H x (x<0.53) and, in addition to the conventional superconducting dome seen in LaFeAsO 1-x F x, we find a second dome in the range 0.21<x<0.53, with a maximum T c of 36 K at x=0.3. Density functional theory calculations reveal that the three Fe 3d bands (xy, yz and zx) become degenerate at x=0.36, whereas the FS nesting is weakened monotonically with x. These results imply that the band degeneracy has an important role to induce high T c.

Original languageEnglish
Article number943
JournalNature communications
Volume3
DOIs
Publication statusPublished - 2012

ASJC Scopus subject areas

  • Chemistry(all)
  • Biochemistry, Genetics and Molecular Biology(all)
  • Physics and Astronomy(all)

Fingerprint Dive into the research topics of 'Two-dome structure in electron-doped iron arsenide superconductors'. Together they form a unique fingerprint.

  • Cite this

    Iimura, S., Matuishi, S., Sato, H., Hanna, T., Muraba, Y., Kim, S. W., Kim, J. E., Takata, M., & Hosono, H. (2012). Two-dome structure in electron-doped iron arsenide superconductors. Nature communications, 3, [943]. https://doi.org/10.1038/ncomms1913