1. Department of Molecular Compound Physics, Center for Physical Sciences and Technology, Saulėtekio Avenue 3, LT-10257 Vilnius, Lithuania
2. Department of Electrical Engineering, KU Leuven, Kasteelpark, Arenberg, 3001 Leuven, Belgium
3. IMEC, Kapeldreef 75, 3001 Leuven, Belgium
4. Institute of Chemical Physics, Faculty of Physics, Vilnius University, Saulėtekio Avenue 9, LT-10222 Vilnius, Lithuania