1. Institute of PhysicsJan Dlugosz University in Czestochowa 13/15, al. Armii Krajowej, Czestochowa, 42200 Poland
2. Department of Optical Glass and CeramicsO.G. Vlokh Institute of Physical Optics 23, Dragomanov str, Lviv, 79005 Ukraine
3. Physics DepartmentOpole University of Technology 75, Ozimska str, Opole, 45370 Poland
4. Department of MechanochemistryInstitute of Geotechnics of Slovak Academy of Sciences 45, Watsonova str, Košice, 04001 Slovakia
5. Faculty of Mathematics and Natural SciencesUniversity of Rzeszow 1, Pigonia str., 35‐310, Rzeszow Poland
6. Faculty of Electronics and Computer TechnologiesIvan Franko National University of Lviv 1, Universytetska str., 79000, Lviv Ukraine
7. Laboratoire Verres et Céramiques UMR‐CNRS 6226, University of Rennes Rennes Cedex, 35042 France