1. Department of Physics, Govt. V.Y.T. P.G. Autonomous College, Durg, Chattisgarh, India;
2. Department of Physics, Lovely Professional University, Phagwara, Punjab, India;
3. Department of Physics, Govt. Vivekanand P.G. College, Manendragarh, Chattisgarh, India;
4. Department of Physics, University of Lucknow, Lucknow, India