Superconductivity and upper fields in Na-doped iron arsenides Eu 1-xNa xFe 2As 2 Article

fiu authors

abstract

  • In this paper, we report a systematic investigation of the crystal structure and superconducting properties of iron-based superconductors Eu 1-xNa xFe 2As 2 (x = 0-0.5). X-ray diffraction patterns indicate that the compounds form the ThCr 2Si 2-type structure with space group I4/mmm. The systematic evolution of the lattice constant demonstrates that the Eu ions are successfully replaced by Na. The use of alkali metal substitution into the Eu site allows us to suppress the magnetic/structural phase transition in the parent compounds and superconductivity reaches as high as 35K with a doping level of x = 0.5. In addition, single crystals of Eu 1-xNa xFe 2As 2 (x = 0, 0.5) have been successfully synthesized using the self-flux method. The upper critical fields have been determined with the magnetic field along the ab-plane and the c-axis, yielding an anisotropy of 1.7. The high upper critical fields and the low superconducting anisotropy of the Na-doped EuFe2As 2 compounds indicate a potential for applications such as the generation of high magnetic fields. © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.

publication date

  • March 1, 2012

Digital Object Identifier (DOI)

volume

  • 14