1. Department of Physics and Materials Science; City University of Hong Kong; 83 Tat Chee Avenue Hong Kong SAR 999077 China
2. College of Materials Science and Engineering; Shenzhen University; Shenzhen 518000 China
3. State Key Laboratory of Advanced Welding and Joining; Harbin Institute of Technology; Harbin 150001 China
4. Shenzhen Research Institute; City University of Hong Kong; Shenzhen 518000 China