1. Institute of Physics, Slovak Academy of Sciences, Dubravska cesta 9, 84511 Bratislava, Slovakia
2. ETH Zurich, Auguste-Piccard-Hof 1, 8093 Zürich, Switzerland
3. Sumy State University, Rymsky-Korsakov 2, 40007 Sumy, Ukraine
4. Center for Nano-diagnostics, Slovak University of Technology in Bratislava, Vazovova 5, 81243 Bratislava, Slovakia
5. Faculty of Mathematics, Physics and Informatics, Comenius University, Mlynska dolina F1, 84248 Bratislava, Slovakia
6. Centre for Advanced Materials Application, Slovak Academy of Sciences, Dubravska cesta 9, 84511 Bratislava, Slovakia