1. Science School
2. Xi’an University of Technology
3. Xi’an 710048
4. People's Republic of China
5. Key Laboratory for Physical Electronics and Devices of the Ministry of Education & School of Science & Shaanxi Key Lab of Information Photonic Technique
6. Department of Physics
7. City University of Hong Kong
8. Kowloon
9. China
10. Department of Electrical Engineering
11. Xi’an Jiaotong University
12. Xi’an 710049