1. Department of Physics, Mount Zion College of Engineering and Technology, Pudukkottai-622507, India
2. Department of Physics, Anna University Chennai: University College of Engineering-Pattukkottai, Rajamadam-614701, India
3. Department of Chemistry, Easwari Engineering College, Ramapuram, Chennai-600089, India
4. Department of Chemistry, Anna University Chennai: University College of Engineering-Pattukkottai, Rajamadam-614701, India
5. Advanced Functional Materials Laboratory, Department of Physics, National Institute of Technology, Tiruchirappalli-620015, India