O.F. Lukashova - Post-gradute Student, Department of Quantum Electronics, Institution of Physics, Nanotechnologies and Telecommunications, St. Petersburg Polytechnic University of Peter the Great. E-mail: olga.lukashova.best@gmail.com D.V. Mokrova - Ph.D. (Phys.-Math.), Department of Quantum Electronics, Institution of Physics, Nanotechnologies and Telecommunications, St. Petersburg Polytechnic University of Peter the Great. E-mail: dashkeria@gmail.com E.T. Aksenov - D.Sc. (Phys.-Math.), Department of Quantum Electronics, Institution of Physics, Nanotechnologies and Telecommunications, St. Petersburg Polytechnic University of Peter the Great. E-mail: et.aksenov@gmail.com