1 Group for Materials Science and Applied Mathematics, Malmö University, S-20506 Malmö, Sweden.
2 Hebei Key Lab of Optic-electronic Information and Materials, The College of Physics Science and Technology, Hebei University, Baoding 071002, People's Republic of China.
3 Division of Mathematical Physics, Department of Physics, Lund University, 221-00 Lund, Sweden.
4 Shanghai EBIT Lab, Institute of Modern Physics, Department of Nuclear Science and Technology, Fudan University, Shanghai 200433, People's Republic of China.
5 Department of Computer Science, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada.
6 Institute of Theoretical Physics and Astronomy, Vilnius University, LT-10222 Vilnius, Lithuania.
7 Chimie Quantique et Photophysique, Université libre de Bruxelles, B-1050 Brussels, Belgium.