1. Department of Physics, H. P. T. Arts and R. Y. K. Science College, Nashik 422005, Maharashtra, India
2. Department of Physics, Indian Institute of Technology, Ropar, Rupnagar 140001, Punjab, India
3. Condensed Matter Theory Group, Materials Theory Division, Department of Physics and Astronomy, Uppsala University, Box 516, SE-75120, Uppsala, Sweden
4. School of Chemical Engineering, The University of Queensland, St Lucia, Brisbane 4072, Australia
5. School of Science and Technology, University of New England, Armidale, New South Wales 2351, Australia