Orbital character variation of the Fermi surface and doping dependent changes of the dimensionality inBaFe2−xCoxAs2from angle-resolved photoemission spectroscopy

From a combination of high resolution angle-resolved photoemission spectroscopy and density functional calculations, we derive information on the dimensionality and the orbital character of the electronic states of ${\text{BaFe}}_{2\ensuremath{-}x}{\text{Co}}_{x}{\text{As}}_{2}$. Upon increasing Co doping, the electronic states in the vicinity of the Fermi level take on increasingly three-dimensional character. Both the orbital variation with ${k}_{z}$ and the more three-dimensional nature of the doped compounds have important consequences for the nesting conditions and thus possibly also for the appearance of antiferromagnetic and superconducting phases.