1. Evatec AG, Hauptstrasse 1a, CH-9477 Trübbach, Switzerland
2. Department of Condensed Matter Physics, Masaryk University, Kotlářska 2, CZ-61137 Brno, Czech Republic
3. CEITEC, Masaryk University, Kamenice 5, CZ-60177 Brno, Czech Republic
4. Nanoscale Materials Science, Empa, Überlandstrasse 129, CH-8600 Dübendorf, Switzerland