1. Key Laboratory of Optoelectronics Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China
2. Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, School of Biomedical Engineering, Shenzhen University, Shenzhen 518060, China
3. Faculty of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China