1. Department
of Physics, McGill University, Montréal,
Québec,
Canada H3A 2T8
2. Department
of Microtechnology
and Nanoscience, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden
3. Capres A/S, Diplomvej, Building 373, DK-2800
Kongens Lyngby, Denmark
4. CINF, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark