Extended energy range of Ag quantum-well states in Ag(111)/Au(111)/W(110)

Ag films grown on thin epitaxial Au(111) films on W(110) were investigated by angle-resolved photoemission. Pronounced quantum-well states were observed over an extended energy range of almost 3 eV, much wider than for Ag films on bulk Au(111). This observation is explained by the formation of sp-like quantum-well states in the thin Au film itself; consequently, the Ag quantum-well states exhibit avoided-crossing behavior at appropriate Au-film thicknesses.