1. Department of Physics, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
2. ARC Centre of Excellence on Transformative Meta-Optical Systems, Department of Electronic Materials Engineering, Research School of Physics, The Australian National University, Canberra, ACT 2601, Australia
3. Nanoscale Research Facility, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India