Buczynski, Ryszard, <p>1. Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warsaw, Poland</p><p class="Affiliation">2. Department of Glass, Łukasiewicz Research Network - Institute of Microelectronics and Photonics, al. Lotnikow 32/46, 02‑668, Warsaw, Polan, Poland