1. Laboratory of Photonics and Interfaces Institute of Chemical Sciences and Engineering; School of Basic Sciences; Ecole Polytechnique Fédérale de Lausanne (EPFL); 1015 Lausanne Switzerland
2. Energy Research Institute at NTU (ERI@N); Nanyang Technological University; Research Techno Plaza; 50 Nanyang Drive Singapore 637553 Singapore
3. Laboratory for Thin Films and Photovoltaics; Empa-Swiss Federal Laboratories for Materials Science and Technology; Ueberlandstrasse 129 8600 Dübendorf Switzerland
4. Institute of Computational Physics; Zurich University of Applied Sciences (ZHAW); Wildbachstrasse 21 8401 Winterthur Switzerland
5. School of Materials Science and Engineering; Nanyang Technological University (NTU); Block N4.1, Nanyang Avenue Singapore 639798 Singapore
6. Department of Materials Science and Engineering; College of Engineering; Peking University; Beijing 100871 China