1. Collaborative
Innovation Center for Optoelectronic Semiconductors and Efficient
Devices, Department of Physics, Xiamen University, Xiamen 361005, China
2. International
Center for Quantum Design of Functional Materials (ICQD), and Synergetic
Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
3. Department
of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, United States
4. Ames Laboratory - US DOE, Ames, Iowa 50011, United States