1. Kavli Institute of Nanoscience, Delft University of Technology, P.O. Box 5046, 2600 GA Delft, Netherlands.
2. Department of Physics, University of Regensburg, Regensburg, Germany.
3. Instituto de Ciencia Molecular (ICMol), Universitat de Valencia Catedrático José Beltrán 2, 46980 Paterna, Spain.
4. Institute of Magnetism, National Academy of Sciences and Ministry of Education and Science, 03142 Kyiv, Ukraine.