1. Centre for Nanotechnology Research, Vellore Institute of Technology (VIT), Vellore 632014, Tamil Nadu, India
2. NanoScience Technology Center, University of Central Florida, Orlando, Florida 32826, Unites States
3. Functional Materials Division, CSIR-Central Electrochemical Research Institute, Karaikudi 630003, Tamil Nadu, India
4. School of Physics, University of Hyderabad, Gachibowli, Hyderabad 500046, India
5. Thin Film Magnetism Group, Cavendish Laboratory, Department of Physics, University of Cambridge, Cambridge CB3 0HE, U.K.
6. Climate Change Technology Research Division, Korea Institute of Energy Research, Yuseong-gu, Daejeon 305-343, South Korea