1. School of Physics and Innovation Institute Huazhong University of Science and Technology Wuhan Hubei 430074 P. R. China
2. Paul C. Lauterbur Research Center for Biomedical Imaging Institute of Biomedical and Health Engineering Shenzhen Institutes of Advanced Technology Chinese Academy of Sciences Shenzhen Guangdong 518055 P. R. China
3. School of Electrical and Electronic Engineering Huazhong University of Science and Technology Wuhan Hubei 430074 P. R. China
4. Wuhan Shuneng New Material Co. Ltd. Wuhan Hubei 430074 P. R. China