V.I. Parfenov1, Bui Trong Tien2, Cong Minh Tuan3, A.V. Terekhov4
1,2 Voronezh State University (Voronezh, Russia)
2 National Research University “MPEI” (Moscow, Russia)
1 vip@phys.vsu.ru, 2 trongtienpt98@gmail.com, 3 kongm@mpei.ru, 4 aleksandr-terekhov@ya.ru