1. Department of Physics, NAVKIS PU Academy, Mysore 570010, Karnataka, India.
2. Department of Physics, Karnataka Science College, Dharwad 580003, Karnataka, India.
3. Department of Physics, B V B College of Engineering and Technology, Hubli 580031, Karnataka, India.
4. Department of Chemistry, R V College of Engineering, Bangalore 560059, Karnataka, India.
5. Department of Physics, M S Ramaiah Institute of Technology, Bangalore 560054, Karnataka, India.