[1] Indian Inst Technol, Dept Phys, New Delhi 110016, India
[2] Inter Univ Accelerator Ctr, Div Mat Sci, New Delhi 110067, India
[3] Natl Inst Technol, Dept Phys, Kurukshetra 136119, Haryana, India
[4] Malaviya Natl Inst Technol, Dept Phys, Jaipur 302017, Rajasthan, India
[5] GB Pant Univ Ag & Tech, Dept Phys, Pantnagar 263145, Uttar Pradesh, India