Electronic structure of electron doped BaAs$_{2}$Fe$_{2}$ superconductors revealed by Angle Resolved Photoemission

The electronic structure in the normal state of Co-doped BaAs$_{2}$Fe$_{2}$ superconductors has been measured by Angle Resolved photoemission (ARPES). Co doping on the Fe site results in electron doping [A. S. Sefat et al., Phys. Rev. Lett. 101, 117004 (2008)]. The data qualitatively reveal that Co-doping results in raising the chemical potential, as expected with electron doping. The Fermi surface topology and the possible relevance to the mechanism of spin fluctuation will also be discussed.