1. Leibniz Institute of Photonic Technology e.V. Albert‐Einstein‐Str. 9 07745 Jena Germany
2. Otto Schott Institute of Material ResearchFraunhoferstr.6Friedrich‐Schiller‐University 07743 Jena Germany
3. Abbe Center of PhotonicsFriedrich‐Schiller‐University Max‐Wien‐Platz 1 07743 Jena Germany
4. Institute of Photonics and Optical Science (IPOS) and School of PhysicsA28 Physics Rd, The University of Sydney NSW 2006 Australia
5. Institute of MaterialsEcole Polytechnique Fédérale de Lausanne (EPFL) Lausanne CH 1015 Switzerland