1. Department of Physics, Indian Institute of Engineering Science and Technology (IIEST), Shibpur, Howrah 711103, West Bengal, India
2. Theoretical Sciences Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru 560064, Karnataka, India
3. Department of Physics, University of Calcutta, 92 A. P. C. Road, Kolkata 700009, West Bengal, India