1. Academy of Scientific and Innovative Research (AcSIR), CSIR- National Physical Laboratory (CSIR-NPL) campus, New Delhi, India
2. CSIR-National Physical Laboratory, Dr. K. S. Krishnan Marg, New Delhi India
3. Physics Department, Deshbandhu College (University of Delhi), New Delhi, India
4. Department of Physical Chemistry, Darmstadt University of Technology, Darmstadt, Germany