1. Institute of Geotechnics, Slovak Academy of Sciences, Watsonova 45, 040 01 Košice, Slovakia
2. Institute of Electronics and Photonics, Slovak University of Technology, Ilkovičová 3, 812 19 Bratislava, Slovakia
3. FZU—Institute of Physics of the Czech Academy of Sciences, Cukrovarnická 10/112, 162 00 Prague, Czech Republic
4. Central European Institute of Technology, Brno University of Technology, Purkynova 123, 612 00 Brno, Czech Republic
5. Institute of Material Science of Seville (CSIC-US), Américo Vespucio 49, 41092 Seville, Spain
6. Institute of Materials Research, Slovak Academy of Sciences, Watsonova 47, 040 01 Košice, Slovakia