1. Department of Physics, Indian Institute of Technology Kharagpur, Kharagpur 721302, India
2. Łukasiewicz Research Network − PORT Polish Centre for Technology Development, Stabłowicka 147, 54-066 Wrocław, Poland
3. School of Nano Science and Technology, Indian Institute of Technology Kharagpur, Kharagpur 721302, India
4. Surface Physics & Material Science Division, Saha Institute of Nuclear Physics, A CI of Homi Bhabha National Institute, 1/AF Bidhannagar, Kolkata 700064, India