Affiliation: | 1. Centre of Low Temperature Physics, Institute of Experimental Physics, Slovak Academy of Sciences, Watsonova 47, 040 01 Ko?ice, Slovakia;2. Centre of Low Temperature Physics, Faculty of Science, P. J. ?afárik University, Park Angelinum 9, SK-04154 Ko?ice, Slovakia;3. Materials Science Division, Argonne National Laboratory, Argonne, IL 60439, USA |