1. Centre for Quantum Dynamics, Griffith University, Brisbane 4111, Australia
2. Department of Physics and Astronomy and ARC Centre for Engineered Quantum Systems, Macquarie University, NSW 2109, Australia
3. Istituto Italiano di Tecnologia, Via Morego 30, 16136 Genova, Italy
4. Kalsruhe Institute of Technology, Kalsruhe, Baden-Wuerttemberg, Germany
5. Centro de Física de Materiales (MPC) and Donostia International Physics Center (DIPC), 20018 Donostia-San Sebastián, Spain
6. IKERBASQUE, Basque Foundation for Science, 48013 Bilbao, Spain
7. Institute for Quantum Optics and Quantum Information of the Austrian Academy of Sciences, A-6020 Innsbruck, Austria