1. Department of Physics and Astronomy
2. Wright Center for Photovoltaics Innovation and Commercialization
3. The University of Toledo
4. Toledo
5. USA
6. School of Electronic Science and Engineering
7. Southeast University
8. Nanjing 210096
9. China
10. Key Laboratory of Artificial Micro/Nano Structures of Ministry of Education
11. School of Physics and Technology
12. Wuhan University
13. Wuhan 430072