1. School of Optical-Electrical and Computer Engineering
2. University of Shanghai for Science and Technology
3. Shanghai 200093
4. P. R. China
5. WPI-Advanced Institute for Materials Research
6. Tohoku University
7. Sendai 980-8577
8. Japan
9. School of Materials Science and Engineering
10. Shanghai Jiao Tong University
11. Shanghai 200030
12. China
13. PARC
14. Graduate School of Engineering
15. Osaka University
16. Osaka 565-0871
17. Department of Physics