K.I. Kisilenko – Post-graduate Student, Nizhny Novgorod State Technical University them. R.E. Alekseev

G.S. Malyshev – Post-graduate Student, Nizhny Novgorod State Technical University them. R.E. Alekseev

А.S. Raevsky – Dr.Sc. (Phys.-Math.), Professor, Head of Department «Physics and Technology of Optical Communication»,  Nizhny Novgorod State Technical University them. R.E. Alekseev

S.B. Raevsky – Dr.Sc. (Eng.), Honored Worker of Science of the Russian Federation, Professor,  Nizhny Novgorod State Technical University them. R.E. Alekseev

E-mail: physics@nntu.nnov.ru