1. Department of Electronics and Communication Engineering, Manav Rachna International Institute of Research and Studies (MRIIRS) 1 , Faridabad, Haryana 121004, India
2. Department of Physics, University of Konstanz 2 , Universität Str. 10, D-78457 Konstanz, Germany
3. Department of Pure and Applied Physics, Guru Ghasidas Vishwavidyalaya 3 , Bilaspur, Chhattisgarh 495009, India