1. Department of Technical Physics, L.N. Gumilyov Eurasian National University, Satpayev Str. 2, Astana 010008, Kazakhstan
2. School of Advanced Manufacturing Technologies, National Tomsk Polytechnic University, Tomsk 634050, Russia
3. Vinogradov Institute of Geochemistry, Siberian Branch of Russian Academy of Sciences, Favorskii Str. 1a, Irkutsk 664033, Russia
4. Institute of Solid State Physics, University of Latvia, Kengaraga 8, LV-1063 Riga, Latvia