Superconductivity at 22 K in Co-doped BaFe2As2 crystals.
Here we report bulk superconductivity in BaFe1.8Co0.2As2 single crystals below Tc=22 K, as demonstrated by resistivity, magnetic susceptibility, and specific heat data. Hall data indicate that the dominant carriers are electrons, as expected from simple chemical reasoning. This is the first example of superconductivity induced by electron doping in this family of materials. In contrast with cuprates, the BaFe2As2 system appears to tolerate considerable disorder in the FeAs planes. First principles calculations for BaFe1.8Co0.2As2 indicate the interband scattering due to Co is weak.
Materials Science & Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA.
Athena S
AS
Sefat
Rongying
R
Jin
Michael A
MA
McGuire
Brian C
BC
Sales
David J
DJ
Singh
David
D
Mandrus