1. Peter Gruenberg Institute 9 (PGI-9), Forschungszentrum Juelich, 52428 Juelich, Germany
2. Interdisciplinary Nanoscience Center (iNANO), Aarhus University, 8000 Aarhus C, Denmark
3. IHP - Leibniz Institut für innovative Mikroelektronik, Im Technologiepark 25, 15236 Frankfurt (Oder), Germany
4. Pollard Institute, School of Electronic and Electrical Engineering, University of Leeds, Leeds LS2 9JT, United Kingdom
5. Dipartimento di Scienze, Università Roma Tre, Viale G. Marconi 446, 00146 Roma, Italy