1. Peter Grünberg Institute 9 (PGI-9), Forschungszentrum Jülich, 52425 Jülich, Germany
2. Department of Physics, RWTH Aachen University, 52074 Aachen, Germany
3. Peter Grünberg Institute 1 (PGI-1) and Institute for Advanced Simulation 1 (IAS-1), Forschungszentrum Jülich and JARA, 52425 Jülich, Germany
4. II. Institute of Physics, University of Göttingen, 37077 Göttingen, Germany
5. Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden, Germany
6. Department of Applied Physics, Aalto University School of Science, P.O. Box 11100, 00076 Aalto, Finland
7. Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
8. International Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan