1. Chair in Hybrid Nanosystems, Nano-Institute Munich, Faculty of Physics, Ludwig-Maximilians-University Munich, Munich 80539, Germany
2. Central European Institute of Technology, Brno University of Technology, 61200 Brno, Czech Republic
3. Institute of Physical Engineering, Faculty of Mechanical Engineering, Brno University of Technology, 61669 Brno, Czech Republic
4. School of Physics and Astronomy, Monash University, Clayton, Victoria 3800, Australia
5. Department of Physics, Imperial College London, London SW7 2AZ, United Kingdom
6. Departamento de Física, Universidade Federal de Pernambuco, 50670-901 Recife, PE, Brazil