1. Key Laboratory of Physical Electronics and Devices of Ministry of Education, School of Electronic and Information Engineering, Xi’an Jiaotong University, Xi’an, Shaanxi 710049, China
2. School of Science, Xi’an Jiaotong University, Xi’an, Shaanxi 710049, China
3. Shaanxi Institute for Food and Drug Control, Xi’an, Shaanxi 710065, China