1. Department of Physics, Government First Grade College, Davangere, Karnataka, India;
2. Department of Physics, Ghousia College of Engineering, Ramanagrarm, Karnataka, India;
3. Department of Physics, Shri Shirdi Sai Institute of Science and Engineering, Anantapuramu, Andhra Pradesh, India;
4. VTU P.G Centre, Doddabalapur, Karnataka, India