*Hamid Mansoor Ghaithan1,2, Zeyad A. Alahmed1, Saif M. H. Qaid1, Mahmoud Hezam3, Abdullah S. Aldwayyan1,3
(1. Physics and Astronomy Department, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia , 2. Physics Department, College of Education and linguistic, Amran University, Amran, Yemen, 3. King Abdullah Institute for Nanotechnology, King Saud University, P.O. Box 2454, Riyadh 11451, Saudi Arabia)