1. Institute of Computational Physics, Zurich University of Applied Sciences, Wildbachstr. 21, 8401 Winterthur, Switzerland
2. Fluxim AG, Loft 313, Katharina-Sulzer-Platz 2, 8400 Winterthur, Switzerland
3. Institute of Physics, University of Augsburg, 86135 Augsburg, Germany
4. Instituto de Ciencia Molecular, Universidad de Valencia, C/J. Beltrán 2, 46980 Paterna, Spain