1. Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University, Torun, Poland;
2. Institute of Mathematics and Physics, UTP University of Science and Technology, Bydgoszcz, Poland;
3. Institute of Physics, Kazimierz Wielki University, Bydgoszcz, Poland;
4. Faculty of Chemistry, Taras Shevchenko National University of Kyiv, Kyiv, Ukraine