1. Multifunctional Materials Laboratory, Department of Physics, Indian Institute of Technology Madras, Chennai 600036, India
2. Centre for Automotive Energy Materials, International Advanced Research Centre for Powder Metallurgy and New Materials, IITM Research Park, Chennai 600113, India
3. Centre for Nanomaterials, International Advanced Research Centre for Powder Metallurgy and New Materials, Balapur P.O, Hyderabad 500005, India
4. Department of Physics, Nano Functional Materials Technology Centre and Materials Science Research Center, Indian Institute of Technology Madras, Chennai 600036, India