1. Department of Physics, University of Agriculture Faisalabad, Faisalabad 38040, Pakistan
2. Department of Electrical Engineering, College of Engineering, King Saud University, Riyadh 11362, Saudi Arabia
3. Department of Physics and Astronomy, College of Science, King Saud University, P.O. Box 2455, 11451 Riyadh, Saudi Arabia
4. School of Mathematics and Physics, University of Science and Technology, Beijing 100083, China