State Key Laboratory of Superlattices and Microstructures,Institute of semiconductors,Chinese Academy of Sciences,P.O.Box 912,Beijing 100083,China;
State Key Laboratory of Superlattices and Microstructures,Institute of semiconductors,Chinese Academy of Sciences,P.O.Box 912,Beijing 100083,China;
Physics and Electronic Engineering College,Henan Normal University,Xinxiang 453007,China;
State Key Laboratory of Superlattices and Microstructures,Institute of semiconductors,Chinese Academy of Sciences,P.O.Box 912,Beijing 100083,China;
School for Engineering of Matter,Transport and Energy,Arizona State University,Tempe,Arizona 85287,USA;
Physics and Electronic Engineering College,Henan Normal University,Xinxiang 453007,China;
State Key Laboratory of Superlattices and Microstructures,Institute of semiconductors,Chinese Academy of Sciences,P.O.Box 912,Beijing 100083,China;
