1. Centre for Clean Energy and Nano Convergence, Hindustan Institute of Technology and Science, Chennai 603103, India
2. Condensed Matter Theory Group, Department of Physics and Astronomy, Uppsala University, Box 516, S-75120 Uppsala, Sweden
3. School of Aeronautical Sciences, Hindustan Institute of Technology and Science, Chennai 603103, India
4. Department of Physics, Konkuk University, Seoul 05029, Republic of Korea
5. Department of Physics, Indian Institute of Technology (IIT) Ropar, Rupnagar 140001, Punjab, India
6. School of Chemical Engineering, The University of Queensland, St Lucia, Brisbane 4072, Australia
7. School of Science and Technology, University of New England, Armidale, New South Wales 2351, Australia