1. Division
of Physics and Applied Physics, School of Physical and Mathematical
Sciences, Nanyang Technological University, 21 Nanyang Link, 637371 Singapore
2. Chemistry
Department, M. V. Lomonosov Moscow State University, Leninskie
Gory, 1-3, 119991, Moscow, Russia
3. Centre
for Ion Beam Applications, Department of Physics, Faculty of Science, National University of Singapore, 2 Science Drive 3, 117542 Singapore
4. Dpto.
CITIMAC, Facultad de Ciencias, Universidad de Cantabria, Avda. Los
Castros, s/n 39005 Santander, Spain
5. Materials
Research Institute and School of Physics and Astronomy, Queen Mary University of London, Mile End Road, London E1 4NS, United Kingdom
6. NOVITAS,
Nanoelectronics Center of Excellence, School of Electrical and Electronic
Engineering, Nanyang Technological University, 639798 Singapore
7. MajuLab,
CNRS-UNS-NUS-NTU
International Joint Research Unit, UMI 3654, Singapore