1. Technical University of Munich, TUM School of Natural Sciences, Physics Department, D-85748 Garching, Germany
2. Laboratoire National des Champs Magnétiques Intenses (LNCMI-EMFL), CNRS, UGA, 38042 Grenoble, France
3. Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
4. Max-Planck-Institute for Solid State Research, Heisenbergstrasse 1, D-70569 Stuttgart, Germany
5. Technical University of Munich, TUM Center for Quantum Engineering (ZQE), D-85748 Garching, Germany
6. Munich Center for Quantum Science and Technology (MCQST), D-80799 Munich, Germany