1. Max Planck Institute for the Science of Light, Günther-Scharowski-Strasse 1, 91058 Erlangen, Germany
2. University Erlangen-Nuremberg, Institute of Optics,
Information and Photonics, Staudtstrasse 7/B2, 91058 Erlangen, Germany
3. Peter
Grünberg Institute (PGI-9), Forschungszentrum Jülich, D-52425 Jülich, Germany
4. JARA - Fundamentals of Future Information Technologies, D-52425 Jülich, Germany
5. University Erlangen-Nuremberg, Center for Nanoanalysis
and Electron Microscopy, Cauerstrasse 6, 91058 Erlangen, Germany
6. Helmholtz Centre Berlin for Materials and Energy, Hahn-Meitner Platz 1, 14109 Berlin, Germany