N. A. Savastenko
ISEU BSU, Minsk, Belarus, e-mail: nataliesavastenko@iseu.by
Belarus

I. I. Filatova
B. I. Stepanov Institute of Physics of the National Academy of Sciences of Belarus, Minsk, Belarus, e-mail:i.filatova@dragon.bas-net.by
Belarus

V. A. Lyushkevich
B. I. Stepanov Institute of Physics of the National Academy of Sciences of Belarus, Minsk, Belarus, e-mail:i.filatova@dragon.bas-net.by
Belarus

N. I. Chubrik
B. I. Stepanov Institute of Physics of the National Academy of Sciences of Belarus, Minsk, Belarus, e-mail:i.filatova@dragon.bas-net.by
Belarus

M. T. Gabdullin
National Nanotechnology Laboratory of Open Type, Al-Farabi Kazakh National University, Almaty, Kazakhstan
Kazakhstan

T. S. Ramasanov
National Nanotechnology Laboratory of Open Type, Al-Farabi Kazakh National University, Almaty, Kazakhstan
Kazakhstan

Kh. A. Abdullin
National Nanotechnology Laboratory of Open Type, Al-Farabi Kazakh National University, Almaty, Kazakhstan
Kazakhstan

Zh. K. Kalkosova
National Nanotechnology Laboratory of Open Type, Al-Farabi Kazakh National University, Almaty, Kazakhstan
Kazakhstan