**5. Conclusions**


**Author Contributions:** Conceptualization, H.H. and Y.I.; methodology, D.N., A.M. and Y.I.; investigation, D.N. and A.M.; writing—original draft preparation, D.N.; writing—review and editing, Y.I. and A.M.; supervision, Y.I. and H.H.; project administration, H.H.; funding acquisition, Y.I. and H.H.

**Funding:** This work was financially supported by German Research Foundation (DFG) under Grants Nos. IV98/8-1, HA1344/39-1.

**Acknowledgments:** Authors are grateful to R. Kulagin and Y. Beygelzimer for fruitful discussion of the material´s mechanical properties and to V. Provenzano for the careful editing of the manuscript. This work was partly performed with the support of the Karlsruhe Nano Micro Facility (KNMF), a Helmholtz Research Infrastructure at the Karlsruhe Institute of Technology (KIT).

**Conflicts of Interest:** The authors declare no conflict of interest.
