1. Photonics Institute TU Wien Gusshausstrasse 27‐29/387 Vienna A‐1040 Austria
2. Institute for Theoretical Physics Johannes Kepler University Altenbergerstraße 69 Linz A‐4040 Austria
3. Institute of Inorganic Chemistry Department of Chemistry and Applied Bioscience, ETH Zürich Vladimir Prelog Weg 1 Zürich CH‐8093 Switzerland
4. Empa‐Swiss Federal Laboratories for Materials Science and Technology Überlandstrasse 129 Dübendorf CH‐8600 Switzerland
5. Center for Physical Sciences & Technology Savanoriu Ave. 231 Vilnius LT‐02300 Lithuania