1. Physikalisches Institut, Universität Freiburg, Herrmann-Herder-Strasse 3, D-79104 Freiburg, Germany
2. Department of Chemistry, The University of British Columbia, 2036 Main Mall, Vancouver, BC, Canada V6T 1Z1
3. FIT Freiburg Center for Interactive Materials and Bioinspired Technologies, University of Freiburg, Georges-Köhler-Allee 105, 79110 Freiburg, Germany
4. Fraunhofer IWM, MikroTribologie Centrum μTC, Wöhlerstrasse 11, D-79108 Freiburg, Germany