1. Institute for Solar Energy Research Hamelin (ISFH), Am Ohrberg 1, 31860 Emmerthal, Germany
2. Leibniz University of Hanover (LUH), Institute for Solid State Physics, Appelstraße 2, 30167 Hannover, Germany
3. Physikalisch-Technische Bundesanstalt (PTB), Bundesallee 100, 38116 Braunschweig, Germany
4. The Australian National University (ANU), College of Engineering and Computer Science, Canberra, ACT 0200, Australia