1. Department of Physics, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
2. Nanoscale Research Facility, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
3. Max Planck Institute for the Science of Light, Günther-Scharowsky-Straße 1, 91058 Erlangen, Germany
4. Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Institute of Optics, Information and Photonics, Staudtstr. 7/B2, 91058 Erlangen, Germany
5. Helmholtz Center for Materials and Energy, Institute–Nanoarchitectures for energy conversion, Hahn-Meitner-Platz 1, D-14109 Berlin, Germany