1. Department of Chemical and Biological Physics
2. Weizmann Institute of Science
3. Rehovot 76100
4. Israel
5. Department of Engineering “Enzo Ferrari”
6. University of Modena and Reggio Emilia
7. Modena 41125
8. Italy
9. Department of Materials and Interfaces
10. Department of Applied Physics
11. Center for Nano Science and Nanotechnology
12. Hebrew University of Jerusalem
13. Jerusalem 91904