1Department of Biomedical Engineering, School of Medicine, Shenzhen University, Shenzhen 518060, China
2Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronics Engineering, Shenzhen University, Shenzhen 518060, China
3Department of Electronic Engineering, The Chinese University of Hong Kong, Hong Kong, China