1. HKUST-Shenzhen Research Institute, No.
9 Yuexing 1st RD, South Area, Hi-tech Park, Nanshan, Shenzhen 518057, China
2. Department
of Physics, Department of Chemistry, Division of Life Science, State
Key Laboratory of Molecular Neuroscience, Institute for Advanced Study,
Institute of Molecular Functional Materials, Division of Biomedical
Engineering, The Hong Kong University of Science and Technology, Clear Water Bay,
Kowloon, Hong Kong, China
3. Guangdong
Innovative Research Team, SCUT-HKUST Joint Research Laboratory, State
Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou 510640, China