Band structure of the heavily-electron-doped FeAs-based Ba(Fe,Co) ₂As₂ Superconductor suppresses antiferromagnetic correlations

In the heavily-electron-doped regime of the Ba(Fe,Co)₂As ₂ superconductor, three hole bands at the zone center are observed and two of them reach the Fermi level. The larger hole pocket at the zone center is apparently nested with the smaller electron pocket around the zone corner. However, the (π,0) Fermi surface reconstruction reported for the hole-doped case is absent in the heavily-electron-doped case. This observation shows that the apparent Fermi surface nesting alone is not enough to enhance the antiferromagnetic correlation as well as the superconducting transition temperature.