1. Research Center for Advanced Functional Materials and Devices; Shenzhen Key Laboratory of Advanced Materials; School of Materials Science and Engineering; Harbin Institute of Technology; Shenzhen 518055 P. R. China
2. Cbrite Inc. 421 Pine Avenue; Goleta CA 93117 USA
3. Department of Electronic Engineering and Materials Science and Technology Research Centre; The Chinese University of Hong Kong (CUHK); Shatin Hong Kong China