1. Friedrich Schiller University, Institute of Solid State Physics, 07743 Jena, Germany
2. Friedrich Schiller University, Institute of Applied Physics, Abbe Center of Photonics, 07743 Jena, Germany
3. University of Brescia, Department of Information Engineering and INO−CNR, 25121 Brescia, Italy
4. Politecnico di Milano, Department of Physics, 20133 Milano, Italy
5. Fraunhofer Institute for Applied Optics and Precision Engineering, 07745 Jena, Germany
6. Istituto Italiano di Tecnologia, 16163 Genova, Italy
7. ARC Centre of Excellence for Transformative Meta-Optical Systems (TMOS), Research School of Physics, Australian National University, Canberra, ACT 2601, Australia