1. B. Verkin Institute for Low Temperature Physics and Engineering of the National Academy of Sciences of Ukraine, 47 Nauky Ave., Kharkiv 61103, Ukraine
2. Institute for Physics and Chemistry of Solid State, Uzhhorod National University, 54 Voloshina str., Uzhhorod 88000, Ukraine
3. Institute of Physics, Jan Dlugosz University in Czestochowa, 13/15 Al. Armii Kraiovei, Czestochowa 42200, Poland