1. The MOE Key Laboratory of Weak-Light Nonlinear Photonics
2. School of Physics
3. Nankai University
4. Tianjin 300071, China
5. Institute of Photo-electronic Thin Film Devices and Technology
6. Key Laboratory of Photo-electronic Thin Film Devices and Technology of Tianjin
7. Tianjin 300071, PR China
8. Tianjin Key Laboratory of Photoelectronic Materials and Device
9. Tianjin University of Technology
10. Tianjin 300191, China