Diffraction effects in angle-resolved photoemission spectroscopy

Abstract The surface sensitivity of many ultra–high vacuum spectroscopies comes from the short mean free path of either scattered or emitted electrons. The energy of the electrons ranges from a few electron volts to a few hundred electron volts. In this energy range, the wavelength of the electron is about the same order of magnitude as atomic spacings in a solid. Hence, as the electron undergoes strong electron‐electron inelastic collisions, which limit its mean free path, it also diffracts strongly from the arrays of ordered or disordered surface atoms.