1. van der Waals-Zeeman Institute, Institute of Physics, University of Amsterdam, Amsterdam 1098XH, The Netherlands
2. Van’t Hoff Institute for Molecular Science, University of Amsterdam, Amsterdam 1098XH, The Netherlands
3. Université de Lyon, Ecole Normale Supérieure de Lyon, Université Claude Bernard, CNRS, Laboratoire de Physique, Lyon F-69342, France