1. Institute of Physics and Chemistry of Metals, University of Silesia, Bankowa 12, 40-007 Katowice, Poland
2. Department of Experimental Physics, Institute of Physics, Technical University of Lublin, Nadbystrzycka 38, 20-618 Lublin, Poland
3. Warsaw University of Technology, Department of Materials Science and Engineering, Wołoska 141, 02-507 Warsaw, Poland