1. Key Laboratory of Brain-like Neuromorphic Devices and Systems of Hebei Province, College of Electron and Information Engineering, Hebei University, Baoding 071002, China
2. College of Physics Science and Technology, Hebei University, Baoding 071002, China
3. School of Materials Science and Engineering, China University of Mining and Technology, Xuzhou 221116, China
4. School of mathematics and physics, Anyang Institute of Technology, Anyang 455099, China
5. School of Physics, Beihang University, Beijing 100191, China