Abstract: The mechanism of high temperature superconductivity is a key issue in condensed matter physics. In order to reveal the orders and interactions which are essential to superconductivity, a direct way is to unravel the electronic structure of the high temperature superconducting materials. In this paper, we review some of the studies on high-temperature cuprate superconductors and iron-based superconductors via angle-resolved photoemission spectroscopy (ARPES) and resonant elastic X- ray scattering (REXS). We mainly focus on Bi2Sr2CaCu2O8+ , YBa2Cu3O7??x/La0:7Ca0:3MnO3 heterostructures and FeSe lms grown on SrTiO3 substrate.

Key words: high-temperature cuprate superconductors; iron-based superconductors; electronic structure; angle-resolved photoemission spectroscopy; resonant elastic X-ray scattering