Electronic structure of thin ytterbium layers on W(1Â 1Â 0): A photoemission study

In the present work we report on high-quality results of angle-resolved photoemission studies of thin Yb layers (1-3 ML thick) on a W(1 1 0) substrate. Growth of the thin Yb layers was monitored via permanent measurements of photoemission spectra during Yb deposition. This method allows to monitor the thickness of the deposited Yb with very high accuracy due to strong layer-dependent binding energy shifts of the Yb 4f emission. Contrasting to Ce/W(1 1 0) no hybridization of the 4f states with the own 6s-derived band is observed for the Yb layers. Instead, a splitting of the Yb 4f7/2 emission is observed around the Γ-point that is due to interactions with the W 5d-derived substrate band and could quantitatively be described in the framework of the Periodic Anderson model.