1. Department of Physics
2. Sri Venkateswara University
3. Tirupati-517 502
4. India
5. School of Semiconductor and Chemical Engineering
6. Semiconductor Physics Research Center (SPRC)
7. Chonbuk National University
8. Jeonju 561-756
9. Republic of Korea
10. Centre for Nanoscience and Nanotechnology
11. Sathyabama University
12. Chennai-600119