Key Laboratory for Magnetism and Magnetic Materials of MOE Lanzhou University Lanzhou 730000 China;
Guangzhou Newlife Magnet Electricity Co. Ltd. Guangzhou 511356 China;
Key Laboratory for Magnetism and Magnetic Materials of MOE Lanzhou University Lanzhou 730000 China;
Key Laboratory for Magnetism and Magnetic Materials of MOE Lanzhou University Lanzhou 730000 China;
Key Laboratory of Special Function Materials and Structure Design(Ministry of Education) Lanzhou University Lanzhou 730000 China;