1. Institute of Physics, National Academy of Sciences of Ukraine, 46, pr. Nauky, 03028 Kyiv, Ukraine
2. Lashkaryov Institute of Semiconductor Physics, National Academy of Sciences of Ukraine, 45, pr. Nauky, 03028 Kyiv, Ukraine
3. Department of Physics and Mathematics, Center for Photonics Sciences, University of Eastern Finland, Yliopistokatu 7, JoensuuFI 80101, Finland
4. Department of Microelectronics, Igor Sikorsky Kyiv Polytechnic Institute, pr. Beresteiskyi 37, 03056Kyiv, Ukraine