1. University Department of Physics, T. M. Bhagalpur University, Bhagalpur 812007, India
2. Department of Mechanical Engineering, Birla Institute of Technology, Mesra (Patna Campus), Patna 800014, India
3. Department of Physics, S. M. College, Bhagalpur 812001, India
4. Department of Metallurgical Engineering and Materials Science, Indian Institute of Technology, Mumbai 400076, India