1. South China Academy of Advanced Optoelectronics & International Academy of Optoelectronics at Zhaoqing South China Normal University Guangzhou 510006 China
2. Department of Chemical Engineering University of Waterloo Waterloo ON N2L 3G1 Canada
3. School of Materials Science and Engineering Hebei University of Technology Tianjin 300130 China
4. School of Information and Optoelectronic Science and Engineering South China Normal University Guangzhou 510006 China
5. Beijing Synchrotron Radiation Facility Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China
6. Department of Physics Boston College Chestnut Hill MA 02467 USA