1. Hebei Advanced Thin Film Laboratory, Department of Physics, Hebei Normal University, Shijiazhuang City 050024, People’s Republic of China
2. Department of Physics and Electronic Science, Liupanshui Normal University, Liupanshui City 553004, People’s Republic of China
3. State Key Laboratory of Magnetism, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People’s Republic of China