1. Institut für Theoretische Physik and Center for Integrated Quantum Science and Technology (IQST), Universität Ulm, Albert-Einstein Allee 11, 89069 Ulm, Germany
2. Racah Institute of Physics, The Hebrew University of Jerusalem, Jerusalem, 91904 Givat Ram, Israel
3. Institute for Quantum Optics and Center for Integrated Quantum Science and Technology (IQST), Universität Ulm, Albert-Einstein-Allee 11, 89069 Ulm, Germany