1. Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials; Key Laboratory of Cluster Science; Ministry of Education; School of Chemistry and Chemical Engineering; Beijing Institute of Technology; Beijing 100081 P. R. China
2. Laser Micro-/Nano-Fabrication Laboratory; School of Mechanical Engineering; Beijing Institute of Technology; Beijing 100081 P. R. China
3. Key Laboratory for Advanced Materials Processing Technology; Ministry of Education of China; State Key Laboratory of Tribology; Department of Mechanical Engineering; Tsinghua University; Beijing 100084 P. R. China