1. Department of Physics Burdwan Raj College Burdwan 713104 West Bengal India
2. School of Materials Sciences Indian Association for the Cultivation of Science Jadavpur Kolkata 700032 West Bengal India
3. Department of Instrumentation Science Jadavpur University Jadavpur Kolkata 700032 West Bengal India
4. Materials Science Division Department of Physics The University of Burdwan Golapbag Burdwan 713104 West Bengal India