1. Department of Physics, B. S. Abdur Rahman University, Chennai 600048, Tamil Nadu, India
2. Department of Physics, School of Advanced Sciences, VIT University, Vellore 632014, Tamil Nadu, India
3. Mechanical and Industrial Engineering Department, Qatar University, P. O. Box 2713, Doha, Qatar
4. Center for Advanced Materials, Qatar University, P. O. Box 2713, Doha, Qatar