1. State Key Laboratory for Manufacturing Systems Engineering Xi'an Jiaotong University Xi'an Shanxi 710049 People's Republic of China
2. Centre for Disruptive Photonic Technologies Division of Physics and Applied Physics School of Physical and Mathematical Sciences Nanyang Technological University Singapore 637371 Singapore
3. Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province College of Physics and Optoelectronics Engineering Shenzhen University Shenzhen 518060 China
4. Zhejiang Research Institute of Xi'an Jiaotong University Hangzhou Zhejiang 311215 People's Republic of China