1. School of Physics, V.N. Karazin Kharkiv National University, 4, Svobody Square, 61022 Kharkiv, Ukraine
2. Institute for Nanomaterials, Advanced Technologies and Innovation, Technical University of Liberec, 2, Studentska Str., 46117 Liberec, Czech Republic
3. Department of Micro- and Nanoelectronics, National Technical University “Kharkiv Polytechnic Institute”, 2, Kyrpychova Str., 61002 Kharkiv, Ukraine