1. CEITEC BUT, Brno University of Technology, Purkyňova 123, 612 00 Brno, Czechia
2. Center for Memory and Recording Research, University of California San Diego, La Jolla, California 92093-0401, United States
3. Department of Condensed Matter Physics, Faculty of Science, Masaryk University, Kotlářská 2, 611 37 Brno, Czechia
4. Institute of Physical Engineering, Brno University of Technology, Technická 2, 616 69 Brno, Czechia