1. Nano Science Laboratory Institute Instrumentation Centre Indian Institute of Technology Roorkee Roorkee Uttarakhand 247667 India
2. Centre for Nanotechnology Indian Institute of Technology Roorkee Roorkee Uttarakhand 247667 India
3. Department of Physics Indian Institute of Technology Roorkee Roorkee Uttarakhand 247667 India
4. Department of Physics Graphic Era (Deemed to be University) Dehradun Uttarakhand 248002 India
5. Department of Polymer and Process Engineering Indian Institute of Technology Roorkee Roorkee Uttarakhand 247667 India