Surface electronic structure of UGax films

Thin films of UGa2 and UGa3 were prepared by sputter deposition on a Si sub strate and studied by photoemission spectroscopy (XPS and UPS) and by ion s cattering spectroscopy (ISS). The films were prepared from very small sampl es (less than 100 mg) and are practically oxygen-free up to high temperatur es. The study of the electronic structure of clean stoichiometric films rev ealed itinerant character of the 5f electronic states in both compounds. By varying the deposition temperature, we could modify the surface compositio n in the case of UGa3. At high temperatures, the surface was entirely cover ed by a mostly Ga overlayer. (C) 2001 Elsevier Science B.V. All rights rese rved.