1. Electrotechnical Institute Division of Electrotechnology and Materials Science, M. Skłodowskiej-Curie 55/61, 55-369 Wrocław, Poland
2. International Laboratory of High Magnetic Fields and Low Temperatures, Gajowicka 95, 52-421 Wrocław, Poland
3. Electrotechnical Institute, M. Pożaryskiego 28, 04-703 Warszawa, Poland