1. Department of Physics and Centre of Nanotechnology, Indian Institute of Technology, Roorkee, Roorkee 247667, India
2. Indus Synchrotrons Utilization Division, Raja Ramanna Centre for Advanced Technology, Indore 452013, India
3. Laser Biomedical Applications and Instrumentation Division, Raja Ramanna Centre for Advanced Technology, Indore 452013, India
4. National Physical Laboratory (CSIR), Dr K S Krishnan Road, New Delhi 110012, India