1. Technical University of Munich, TUM School of Natural Sciences, Department of Chemistry, Lichtenbergstraße 4, 85748 Garching, Germany
2. Munich Center for Quantum Science and Technology (MCQST), Schellingstraße 4, 80799 München, Germany
3. Wigner Research Centre for Physics, Institute for Solid State Physics and Optics, P.O. Box 49, Budapest H-1525, Hungary
4. Technical University of Munich, Walter Schottky Institut, Am Coulombwall 4, 85748 Garching, Germany
5. Technical University of Munich, TUM School of Natural Sciences, Department of Physics, James-Franck-Straße 1, 85748 Garching, Germany
6. Department of Atomic Physics, Institute of Physics, Budapest University of Technology and Economics, Műegyetem rakpart 3, Budapest H-1111, Hungary