1. School of Nanoscience and Technology, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal 721302, India
2. School of Energy Science and Engineering, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal 721302, India
3. Department of Physics, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal 721302, India
4. Defence Materials and Stores R&D Establishment (DRDO), Kanpur, Uttar Paradesh 208013, India