[1] B. Verkin Institute for Low Temperature Physics and Engineering, National Academy of Sciences of Ukraine, 47 Lenin Ave., Kharkov 61103, Ukraine
[2] Experimental Physics 5, Center for Electronic Correlations and Magnetism, Institute of Physics, University of Augsburg, Augsburg 86159, Germany
[3] Institute of Applied Physics, Academy of Sciences of Moldova, MD-2028 Chisinau, Moldova
[4] Institute of Experimental Mineralogy, Russian Academy of Sciences Chernogolovka, Moscow District 142432, Russia
[5] Moscow State University, Physics Department, Moscow 119991, Russia