1. Beijing Engineering Research Center of Mixed Reality and Advanced DisplaysSchool of Optics and PhotonicsBeijing Institute of Technology Beijing 100081 China
2. Beijing Key Laboratory of Nanophotonics and Ultrafine Optoelectronic SystemsSchool of PhysicsBeijing Institute of Technology Beijing 100081 China
3. Department of Materials Science and Engineering, and Centre for Functional Photonics (CFP)City University of Hong Kong 83 Tat Chee Avenue Kowloon Hong Kong SAR