1. Institute of Physics, Nanotechnologies and Telecommunications, Higher School of Engineering and Physics, Peter the Great St. Petersburg Polytechnic University, St. Petersburg, Russia;
2. Division of Physics of Dielectric and Semiconductors, Ioffe Institute, St. Petersburg, Russia;
3. Faculty of Engineering and Physics, Department of Physics, Amur State University, Blagoveshchensk, Russia;
4. Institute of Chemistry and Chemical Technology, Siberian Branch, Russian Academy of Sciences, Krasnoyarsk, Russia;
5. Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Dubna, Russia