Surface-Effect Characteristics of Photoemission from Clean Copper-Crystal Surfaces

Abstract

With photon energies within 1.5 eV above the threshold, photoelectric yields, as measured from Cu (100) and (111) with obliquely incident light, exhibit strong deviations from the $Y\ensuremath{\propto}{(\ensuremath{\hbar}\ensuremath{\omega}\ensuremath{-}\ensuremath{\phi})}^{2}$ dependence found at normal incidence. A preliminary energy analysis shows the distribution of the emitted electrons to shift towards the high-energy edge when the angle of incidence changes from 0\ifmmode^\circ\else\textdegree\fi{} to 60\ifmmode^\circ\else\textdegree\fi{}. The results are interpreted in terms of a surface photoelectric effect.