1. The MOE Key Laboratory of Weak-Light Nonlinear Photonics
2. TEDA Institute of Applied Physics and School of Physics
3. Nankai University
4. Tianjin 300457
5. China
6. CAS Key Laboratory of Nanosystem and Hierarchical Fabrication
7. CAS Center for Excellence in Nanoscience
8. National Center for Nanoscience and Technology
9. Beijing 100190
10. Faculty of Physics
11. University of Vienna
12. A-1090 Vienna
13. Austria
14. Jožef Stefan Institute