1. State Key Laboratory of Metastable Materials Science and Technology; Yanshan University; Qinhuangdao 066004 China
2. Center for Applied Physics and Technology; College of Engineering; Peking University; Beijing 100871 China
3. New Industry Creation Hatchery Center; Tohoku University; 6-6-4 Aramaki-aza-Aoba Aoba-ku Sendai 980-8579 Japan
4. Department of Physics; Virginia Commonwealth University; Richmond VA 23284 USA