1. Division of Solid-State Electronics, Department of Electrical Engineering, The Ångström Laboratory, Uppsala University, SE-751 03 Uppsala, Sweden
2. Division of Photonics, Department of Applied Physics, School of Engineering Sciences, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden
3. Division of Solar Cell Technology, Department of Materials Science and Engineering, The Ångström Laboratory, Uppsala University, SE-751 03 Uppsala, Sweden