1. Department of Materials Science & Engineering and the Russell Berrie Nanotechnology Institute Technion − Israel Institute of Technology Haifa 3200003 Israel
2. European Synchrotron Radiation Facility BP 220 Grenoble Cedex F‐38043 France
3. Chair for Photonics and Optoelectronics Nano‐Institute Munich Department of Physics Ludwig‐Maximilians‐Universität (LMU) Königinstr. 10 80539 Munich Germany
4. The Nancy and Stephen Grand Technion Energy Program Technion − Israel Institute of Technology Haifa 3200003 Israel