1 Laboratory of Solid-State Optoelectronics Information Technology, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
2 State Key Laboratory on Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
3 Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
4 Institute of Solid State Physics and Center of Nanophotonics, Technische Universität Berlin, Hardenbergstrasse 36, 10623 Berlin, Germany
5 Bimberg Chinese-German Center for Green Photonics of the Chinese Academy of Sciences at CIOMP, Changchun 130033, China