1. Department of Physics, Sona College of Technology, Salem, Tamil Nadu, India
2. Department of Physics, St. Thomas College Palai, Arunapuram, Kottayam, Kerala, India
3. Department of Physics, Condensed Matter Research Laboratory (CMRL), Research Park, Bannari Amman Institute of Technology, Sathyamangalam, Tamil Nadu, India
4. Department of Physics and Research Center, Nesamony Memorial Christian College, Marthandam, Kanyakumari, Tamil Nadu, India