1. Department of Physics, University of Ioannina, P.O. Box 1186, 451 10 Ioannina, Greece
2. Bergische Universität Wuppertal, Macromolecular Chemistry Group and Wuppertal Center for Smart Materials and Systems (cm@s), Gauss-Str. 20, D-42119 Wuppertal, Germany
3. Max Planck Institute for Polymer Research, 55128 Mainz, Germany
4. University Research Center of Ioannina (URCI) − Institute of Materials Science and Computing, 451 10 Ioannina, Greece