Interatomic Resonant Photoemission from Quantum-Well States in Ultrathin Films of Ag on V(100)

Normal emission photoemission spectra from a single ordered monolayer of Ag on V(100) show a sharp and intense peak associated with a quantum-well state. The photon energy dependence of the intensity of this peak shows an identical enhancement profile to the V $3d$ photoemission in the vicinity of the V 3p→3d excitation threshold, characteristic of resonant photoemission. The significance of this result for resonant photoemission characterization of materials is discussed.