1. Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan 430074, P. R. China
2. School of Physics, Huazhong University of Science and Technology, Wuhan 430074, P. R. China
3. School of Physics and Electronic Engineering, Zhengzhou University of Light Industry, Zhengzhou 450002, P. R. China
4. MOE Key Laboratory of Fundamental Physical Quantities Measurement & Hubei Key Laboratory of Gravitation and Quantum Physics, PGMF, Huazhong University of Science and Technology, Wuhan 430074, P. R. China