1. State Key Laboratory of Infrared PhysicsShanghai Institute of Technical PhysicsChinese Academy of Sciences Shanghai 200083 China
2. School of MicroelectronicsUniversity of Science and Technology of China Hefei 230026 China
3. Key Laboratory of Magnetism and Magnetic Materials of the Ministry of EducationSchool of Physical Science and Technology and Electron Microscopy Centre of Lanzhou UniversityLanzhou University Lanzhou 730000 China
4. Shenyang National Laboratory for Materials ScienceInstitute of Metal ResearchChinese Academy of Sciences Shenyang 110016 China
5. University of Chinese Academy of SciencesChinese Academy of Sciences Beijing 100049 China
6. Shanghai Key Laboratory of Multidimensional Information ProcessingDepartment of Electronic EngineeringEast China Normal University Shanghai 200241 China