1. Department of General Physics and Modeling of Physical Processes, National Technical University of Ukraine “Igor Sikorsky Kyiv Polytechnic Institute,” 1 pr. Beresteiskyi 37, Kyiv 03056, Ukraine
2. Felix Bloch Institute for Solid State Physics, University of Leipzig 2 , Linnestrasse. 5, Leipzig 04103, Germany
3. Department of Optics and Spectroscopy, V.E. Lashkaryov Institute of Semiconductor Physics NAS of Ukraine 3 , pr. Nauky 41, Kyiv 03028, Ukraine
4. Department of Analysis of Functional Materials, Institute of Physics of the CAS 4 , Na Slovance 2, 18200, Prague 8, Czech Republic