1. Department of Physics, Saveetha School of Engineering, Saveetha Institute of Medical and Technical Sciences, Thandalam, Chennai 602 105, India
2. Department of Physics, Indira Institute of Engineering and Technology, V.G.R. Nagar, Pandur, Thiruvallur 631 203, India
3. Department of Physics, Rajalakshmi Institute of Technology, Kuthambakkam, Chennai 600 124, India
4. Department of Physics, College of Natural and Computational Science, Wollega University, Nekemte, Ethiopia