1. College of New Materials and New Energies, Shenzhen Technology University, Shenzhen 518118, P. R. China
2. Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, P. R. China
3. College of Engineering Physics, Shenzhen Technology University, Shenzhen 518118, P. R. China
4. Department of Applied Physics and Physico-Informatics, Keio University, Yokohama 223-8522, Japan
5. Keio Institute of Pure and Applied Science, Keio University, Yokohama 223-8522, Japan
6. Center for Spintronics Research Network, Keio University, Yokohama 223-8522, Japan