1. Institute of Nanotechnology Karlsruhe Nano Micro Facility (KNMF); Karlsruhe Institute of Technology (KIT); 76128 Karlsruhe Germany
2. Institute of Microstructure Technology (IMT); Karlsruhe Institute of Technology (KIT); 76128 Karlsruhe Germany
3. Physical Institute and Center for Nanotechnology (CeNTech); Westfälische Wilhelms-Universität; 48149 Münster Germany
4. Institute of Applied Physics (APH); Karlsruhe Institute of Technology (KIT); 76128 Karlsruhe Germany
5. Institute of Photonics and Quantum Electronics (IPQ); Karlsruhe Institute of Technology (KIT); 76128 Karlsruhe Germany
6. Carl Zeiss AG, Corporate Research and Technology; Carl-Zeiss-Promenade 10 07745 Jena Germany