1. Catalan Institute of
Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute
of Science and Technology, Campus UAB, Bellaterra, 08193 Barcelona, Spain
2. Institut d’Électronique,
de Microélectronique et de Nanotechnologie, UMR CNRS 8520, Avenue Poincaré, C.S. 60069, 59652 Villeneuve d’Ascq, France
3. Materials Research and Technology (MRT)
Department, Luxembourg Institute of Science and Technology (LIST), 5, avenue des Hauts-Fourneaux, L-4362 Esch-sur-Alzette, Luxembourg
4. CNRS-Laboratoire
d’Analyse et d’Architecture des Systèmes (LAAS), Université de Toulouse, 7 avenue du colonel Roche, 31400 Toulouse, France
5. Laboratorio de Microscopías Avanzadas (LMA), Instituto de
Nanociencia de Aragon (INA) -ARAID, and Departamento de Física
de la Materia Condensada, Universidad de Zaragoza, 50018 Zaragoza, Spain
6. Institució Catalana de Recerca
i Estudis Avançats (ICREA), 08010 Barcelona, Catalonia, Spain
7. Department of Electronic Materials Engineering, Research
School of Physics and Engineering, The Australian National University, Canberra, ACT 0200, Australia