1. Max Planck Institute for the Science of Light, Staudtstraße 2, 91058 Erlangen, Germany
2. Department of Physics, Friedrich Alexander University Erlangen-Nuremberg, Staudtstraße 5, 91058 Erlangen, Germany
3. Institute for Organic and Biomolecular Chemistry, Tammannstraße 2. 37077 Göttingen, Germany
4. Max Planck Institute for Dynamics and Self-Organization, Am Faßberg 17, 37077 Göttingen, Germany