1. NUSNNI-NanoCore, National University of Singapore, Singapore 117411
2. Department
of Physics, National University of Singapore, Singapore 117551
3. Singapore
Synchrotron Light Source (SSLS), National University of Singapore, 5 Research Link, Singapore 117603
4. SZU-NUS Collaborative Innovation Center for Optoelectronic Science & Technology, Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen, China 518060
5. NUS
Graduate School for Integrative Sciences and Engineering (NGS), National University of Singapore, Singapore 117456
6. Department
of Electrical and Computer Engineering, National University of Singapore, Singapore 117576
7. Department
of Materials Science and Engineering, National University of Singapore, Singapore 117575