1. Department of Physics, Chalmers University of Technology, Fysikgränd 3, 412 96 Gothenburg, Sweden
2. Centre for Molecular Medicine Norway, Faculty of Medicine, University of Oslo, Gaustadalléen 21, 0349 Oslo, Norway
3. Department of Chemistry and Chemical Engineering, Chalmers University of Technology, Kemigården 4, 412 96 Gothenburg, Sweden
4. International Iberian Nanotechnology Laboratory, Av. Mestre José Veiga, 4715-330 Braga, Portugal
5. Institut für Chemie und Biochemie, Freie Universität Berlin, Takustraße 3, 14195 Berlin, Germany
6. Department of Microtechnology and Nanoscience, Chalmers University of Technology, Kemivägen 9, 412 96, Gothenburg, Sweden
7. National Physical Laboratory, Hampton Road, TW11 0LW Teddington, U.K.
8. Department of Chemistry, Faculty of Mathematics and Natural Sciences, University of Oslo, Sem Sælands vei 26, 0371 Oslo, Norway