Surface states and Fermi surface of ordered<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>γ</mml:mi></mml:math>-like Ce films on W(110)

Abstract

The surface electronic structure of structurally ordered Cerium films deposited on W(110) has been studied along the two surface high-symmetry directions of the close-packed surface. As in other trivalent rare-earth metals a surface state of ${d}_{{z}^{2}}\ensuremath{-}{p}_{z}$ symmetry was found to dominate the electronic structure near the Fermi energy. This surface state lies exactly at the Fermi energy at $\overline{\ensuremath{\Gamma}}$ dispersing towards higher binding energies with increasing wave vector. Its effective mass amounts $(\ensuremath{-}7.4\ifmmode\pm\else\textpm\fi{}1.3)$ times the electron mass. The surface-state induced emission was found to dominate the Fermi-surface cuts near the $\overline{\ensuremath{\Gamma}}$ point of the first surface Brillouin zone (SBZ), while at the $\overline{\ensuremath{\Gamma}}$ point of the second SBZ the surface state lacks intensity.