1. College of Information and Control Engineering, Xi’an University of Architecture and Technology, Xi’an 710055, China
2. Shaanxi Key Laboratory of Nano Materials and Technology, Xi’an, 710055, China
3. School of Microelectronics, Xidian University, Xi’an 710071, China
4. Applied Physics Program, Physical Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia