1. School of Advanced Materials and Nanotechnology, Xidian University, 266 Xinglong Section of Xifeng Road, Xi’an
710126, Shaanxi, People’s Republic of China
2. State Key Discipline Laboratory of Wide Band Gap Semiconductor
Technology, Xidian University, Xi’an 710071, Shaanxi, People’s Republic of China
3. Department of Physics, University of Agriculture Faisalabad,
38000, Faisalabad, Pakistan