15 December 2014

Evidence for extrinsic, impurity segregation at grain boundaries in high current-density K- and Co-doped BaFe2As2

Grain boundaries in BaFe2As2 (122), which is an iron-based superconductor, block current flow. This study, which was a collaboration with a group at Northwestern University, used a Local Electrode Atom Probe (LEAP), which is a relatively new experimental tool, to make a 3-D atom-by-atom reconstruction of a region of a 122 sample that included a grain boundary. The data showed that the chemical composition varied across the grain boundary and in that oxygen was present at the grain boundaries. These variations in composition may contribute to grain boundary's reduced current carrying capacity.

For more information contact David Larbalestier.

Details

  • Research Area: Superconductivity - Applied
  • Research Initiatives: Materials
  • Facility / Program: ASC
  • Year: 2014
Last modified on 4 March 2015