1. Micro‐ and Nanophotonic Materials GroupUniversity of MonsPlace du Parc 20 7000 Mons Belgium
2. Center of PhotonicsInstitute of PhysicsUniversity of BelgradePregrevica 118 11080 Serbia
3. Old World Lab1357 N. Great Neck Road Suite 104 Virginia Beach VA 23454, USA
4. Department of ChemistryKU LeuvenCelestijnenlaan 200D 3001 Heverlee Belgium
5. Department of Physics and AstronomyWashington State UniversityPullman WA 99164 USA
6. Aix Marseille Univ CNRSCentrale Marseille, Institut Fresnel F‐13013 Marseille France
7. Department of PhysicsUniversity of NamurRue de Bruxelles 61 5000 Namur Belgium