1. 3rd Physics Institute and Research Center SCoPE, University of Stuttgart, 70569 Stuttgart, Germany.
2. Max Planck Institute for Solid State Research, 70174 Stuttgart, Germany.
3. Hefei National Laboratory for Physics Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China, Hefei, 230026, China.
4. RUBION, Ruhr-Universität Bochum, 44801 Bochum, Germany.
5. Department of Physics, The City College of New York, CUNY New York, NY 10031, USA.