1. Department of Physics, Krishnath College, Berhampore, Murshidabad 742101, India
2. Department of Physics, Bidhannagar College, EB-2, Sector-1, Salt Lake, Kolkata 700064, India
3. Department of Physics, Kazi Nazrul University, Asansol 713303, India
4. Department of Physics, Visva-Bharati University, Santiniketan 731235, India