1. Department of Electrical Engineering, University of California, Los Angeles, California 90095, USA
2. Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan 430074, China
3. Department of Mechanical and Aerospace Engineering, University of California, Los Angeles, California 90095, USA
4. Beijing National Laboratory of Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
5. National Nanotechnology Research Center, King Abdulaziz City for Science and Technology, Riyadh 11442, Saudi Arabia
6. Inston Inc., Los Angeles, California 90095, USA