1. SDU
Nano Optics, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
2. Laser Zentrum Hannover e.V., 30419 Hannover, Germany
3. ITMO University, Kronverksky
Pr. 49, St. Petersburg 197101, Russia
4. Department
of Photonics Engineering, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
5. National
Centre for Micro- and Nano-Fabrication, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
6. Leibniz University, 30167 Hannover, Germany