1. Institute of Theoretical Physics, Wrocław University of Science and Technology, 50-370 Wrocław, Poland
2. School of Physics, Trinity College Dublin, Dublin 2, D02 PN40, Ireland
3. Institute of Solid State Physics, Technische Universität Berlin, 10623 Berlin, Germany
4. Lehrstuhl für Angewandte Festkörperphysik Ruhr-Universität Bochum, 44780 Bochum, Germany
5. Laboratory for Optical Spectroscopy of Nanostructures, Department of Experimental Physics, Wrocław University of Technology, 50-370 Wrocław, Poland
6. Walter Schottky Institut and Physik Department, Technische Universität München, 85748 Garching, Germany
7. Department Physik, Universität Paderborn, 33098 Paderborn, Germany
8. Université Grenoble Alpes, CNRS, Grenoble INP, Institut Néel, 38000 Grenoble, France