1. Advanced Materials Laboratory, School of Physical Sciences, Periyar University, Salem 636011, Tamilnadu, India
2. Centre for Research and Development, Department of Physics, PRIST deemed to be University, Thanjavur 613403, Tamilnadu, India
3. Department of Chemical and Metallurgical Engineering, School of Chemical Engineering, Aalto University, P.O.
Box 16100, FI-00076 Aalto, Espoo, Finland
4. Department of Physics, Government Arts College, Salem 636007, Tamilnadu, India