I.А. Petrov 1, A.L. Gelgor 2, T.V. Lavrukhin 3

1,2,3 Higher School of Applied Physics and Space Technologies,

Peter the Great St. Petersburg Polytechnic University (Saint-Petersburg, Russia)

1 petrov_ia@spbstu.ru, 2 agelgor@spbstu.ru, 3 lavruhin3.t@edu.spbstu.ru