1. School of Electrical and Electronic Engineering, Anhui Science and Technology University , Bengbu, Anhui 233030 , China
2. Department of Physics, Anhui Normal University , Wuhu, Anhui 241000 , China
3. Department of Physics, Key Laboratory of Intelligent Sensors and Advanced Sensor Materials, Hunan University of Science and Technology , Xiangtan, Hunan 411201 , China
4. School of Physics and Electronic Science, Zunyi Normal University , Zunyi, Guizhou 563006 , China