1. Department of Photonics and Optoinformatics, ITMO University, St. Petersburg 197101, Russia
2. Faculty of Information Technology and Communication Sciences, Tampere University, Tampere FI-33014, Finland
3. Photovoltaics Laboratory, Ioffe Institute, St. Petersburg 194021, Russia
4. Department of Physics and Engineering, ITMO University, St. Petersburg 197101, Russia
5. The Institute of Optics, University of Rochester, Rochester, New York 14627, USA