1. Istituto Officina dei Materiali-CNR; Laboratorio TASC; s.s. 14 km 163.5 34149 Trieste Italy
2. Empa; Swiss Federal Laboratories for Materials Science and Technology; Nanotech@surfaces Laboratory; Ueberlandstrasse 129 8600 Dübendorf Switzerland
3. Dipartimento di Fisica; Università di Trieste; via A. Valerio 2 34100 Trieste Italy
4. Elettra Sincrotrone Trieste; s.s. 14 km 163.5 in Area Science Park, 34149 Trieste Italy
5. Laboratoire de Physique des Solides; CNRS-UMR 8502; Universitè Paris-Sud; 91405 Orsay France