1. Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
2. Laboratory
for fundamental BioPhotonics (LBP), Institute of Bioengineering (IBI),
and Institute of Materials Science (IMX), School of Engineering (STI),
and Lausanne Centre for Ultrafast Science (LACUS), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland