1School of Information Science and Engineering, Shandong Provincial Key Laboratory of Laser Technology and Application, Shandong University, Qingdao, China
2Key Laboratory of Laser & Infrared System (Shandong University), Ministry of Education, Qingdao, China
3Institute of Novel Semiconductors, State Key Laboratory of Crystal Materials, Shandong University, Jinan, China
4Beijing Engineering and Technology Center for Convergence Networks and Ubiquitous Services, SCCE, University of Science and Technology Beijing, Beijing, China