1. Department of Physics, College of Science, Engineering and Technology, University of South Africa, Private Bag X6, Florida, 1710, Science Campus, Christiaan de Wet and Pioneer Avenue, Florida Park, Johannesburg, South Africa
2. Department of Physics, Faculty of Engineering and Technology (ITER), Siksha ‘O’ Anusandhan University, Khandagiri Square, Bhubaneswar, Odisha, 751030, India
3. Department of Material Science and Chemical Engineering, Politecnico di Torino, Torino 10129, Italy