Affiliation: | 1. Department of Physics of Materials, Charles University, Ke Karlovu 5, 12116 Prague, Czech Republic;2. Department of Condensed Matter Physics, Charles University, Ke Karlovu 5, 12116 Prague, Czech Republic;3. Technical University Bergakademie Freiberg, Gustav-Zeuner-Str. 5, 09599 Freiberg, Germany;4. Institute of Plasma Physics, Czech Academy of Sciences, Za Slovankou 1782/3, 182 00 Prague, Czech Republic |