1. College of Physics and Center of Quantum Materials & Devices Chongqing University Chongqing 401331 P. R. China
2. National Key Laboratory of Integrated Circuits and Microsystems Chongqing 400060 P. R. China
3. Analytical and Testing Center Chongqing University Chongqing 401331 P. R. China
4. School of Chemistry and Chemical Engineering Chongqing University Chongqing 401331 P. R. China
5. School of Science Chongqing University of Posts and Telecommunications Chongqing 400065 P. R. China
6. Chongqing Institute of Green and Intelligent Technology Chinese Academy of Sciences Chongqing 400714 P. R. China
7. College of Materials Science and Engineering Chongqing University Chongqing 400044 P. R. China