1. Solid-State
Physics and Magnetism Section, KU Leuven, BE-3001 Leuven, Belgium
2. EMAT
and CMT Group, Department of Physics, Universiteit Antwerpen, B-2020 Antwerpen, Belgium
3. Department
of Materials Engineering, KU Leuven, BE-3001 Leuven, Belgium
4. Max Planck Institute for Chemical Physics of Solids, D-01187 Dresden, Germany
5. National
Laboratory of Solid State Microstructures, Collaborative Innovation
Center of Advanced Microstructures, and Department of Physics, Nanjing University, Nanjing 210093, China
6. Department
of Physics, Virginia Tech, Blacksburg, Virginia 24061, United States