1. Laser Micro/Nano Fabrication Laboratory, School of Mechanical Engineering, Beijing Institute of Technology, Beijing 100081, P. R. China
2. National Institute of Metrology, Beijing 100029, P. R. China
3. Tianjin Navigation Instruments Research Institute, Tianjin 300131, P. R. China
4. Beijing Institute of Technology Chongqing Innovation Center, Chongqing 401120, P. R. China
5. Yangtze Delta Region Academy of Beijing Institute of Technology, Jiaxing 314019, P. R. China