1 State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Opto-Electronics, Shanxi University, Taiyuan 030006, China; Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China; Liaoning Academy of Materials, Shenyang 110167, China. Electronic address: zhenghan1985@gmail.com.