A.V. Smirnov - Assistant, Saratov State University named after N.G. Chernyshevsky E-mail: methril@yandex.ru I.A. Borodina - Ph. D. (Phys.-Math.), Senior Research Scientist, Laboratory of Physical Acoustics, Saratov branch of Kotel\'nikov IRE of RAS E-mail: borodinaia@yandex.ru B.D. Zaitsev - Dr. Sc. (Phys.-Math.), Professor, Head of Laboratory of Physical Acoustics, Saratov branch of Kotel\'nikov IRE of RAS E-mail: zai-boris@yandex.ru I.E. Kuznetsova - Dr. Sc. (Phys.-Math.), Associate Professor, Leading Research Scientist, Laboratory of Electronic Processes in Semiconductor Devices, Kotel\'nikov IRE of RAS (Moscow) E-mail: kuziren@yandex.ru I.V. Sinev - Ph. D. (Phys.-Math.), Associate Professor, Saratov State University named after N.G. Chernyshevsky E-mail: sineviv@gmail.com A.A. Teplykh - Ph. D. (Phys.-Math.), Senior Research Scientist, Laboratory of Physical Acoustics, Saratov branch of Kotel\'nikov IRE of RAS E-mail: teplykhaa@mail.ru V.V. Kisin - Dr. Sc. (Eng.), Professor, Saratov State University named after N.G. Chernyshevsky E-mail: kisin@sgu.ru