[1] Institute of Applied Physics, Jimei University, Xiamen 361021, China
[2] Sch. of Phys. Science and Technology, Lanzhou University, Lanzhou 730000, China
[3] Institute of Theoretical Physics, Lanzhou University, Lanzhou 730000, China
[4] Center for Nonlinear Studies, Hong Kong Baptist University, Hong Kong, Hong Kong
[5] Department of Physics, Lanzhou University, Lanzhou 730000, China