Study of band structure and Fermi Surface of SrFe$_{2}$As$_{2}$ and BaFe$_{2}$As$_{2 }$by angle-resolved photoemission spectroscopy

Recently superconductivity has been discovered in many iron pnictides when they are properly doped with charge carriers. Thus it is important to understand the undoped parent compounds that also have a puzzling collinear antiferromagnetic ground state. We have performed a systematic angle-resolved photoemission study on some of the parent compounds, mostly on SrFe$_{2}$As$_{2}$ and BaFe$_{2}$As$_{2}$, to investigate their electronic structure and Fermi surface. We will report our experimental results and the comparisons to first-principle band calculations.