1. SMW Group, 3-1 Kr. Barona Street, LV-1050 Riga, Latvia
2. Faculty of Material Science and Applied Chemistry, Institute of Materials and Surface Engineering, Riga Technical University, Paula Valdena Street 3/7, LV-1048 Riga, Latvia
3. Optical Materials Laboratory, Institute of Solid-State Physics, University of Latvia, Ķengaraga Street 8, LV-1063 Riga, Latvia
4. Faculty of Mechanical Engineering, Transport and Aeronautics, Institute of Aeronautics, Riga Technical University, Kipsalas Street 6B, LV-1048 Riga, Latvia