1. Department of Physics, College of Agriculture and Natural Sciences, University of Cape Coast, PMB, Cape Coast, Ghana
2. Department of Mathematics, College of Agriculture and Natural Sciences, University of Cape Coast, PMB, Cape Coast, Ghana
3. Department of Physics, The Pennsylvania State University Altoona, Altoona, Pennsylvania 16601, USA
4. Material Research Institute, The Pennsylvania State University, University Park, Pennsylvania 16802, USA