1. Physics Division, Department of Basic Sciences and Social Sciences, School of Technology, North-Eastern Hill University, Shillong, Meghalaya, India
2. Department of Physics, National Institute of Technology Patna, Patna, Bihar, India
3. Department of Nanotechnology, School of Technology, North Eastern Hill University, Shillong, Meghalaya, India
4. Department of Physics, Sidhu-Kanho-Birsha University, Purulia, West Bengal, India