Extreme sensitivity of superconductivity to stoichiometry in Fe1+δ Se

T. M. McQueen, Q. Huang, V. Ksenofontov, C. Felser, Q. Xu, H. Zandbergen, Y. S. Hor, J. Allred, A. J. Williams, D. Qu, J. Checkelsky, N. P. Ong, R. J. Cava

Research output: Contribution to journalArticlepeer-review

597 Scopus citations


The recently discovered iron arsenide superconductors appear to display a universal set of characteristic features, including proximity to a magnetically ordered state and robustness of the superconductivity in the presence of disorder. Here we show that superconductivity in Fe1+δ Se, which can be considered the parent compound of the superconducting arsenide family, is destroyed by very small changes in stoichiometry. Further, we show that nonsuperconducting Fe1+δ Se is not magnetically ordered down to 5 K. These results suggest that robust superconductivity and immediate instability against an ordered magnetic state should not be considered as intrinsic characteristics of iron-based superconducting systems.

Original languageEnglish (US)
Article number014522
JournalPhysical Review B - Condensed Matter and Materials Physics
Issue number1
StatePublished - Jan 5 2009

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics


Dive into the research topics of 'Extreme sensitivity of superconductivity to stoichiometry in Fe1+δ Se'. Together they form a unique fingerprint.

Cite this