1. Theoretical Physics Division (TPD), PINSTECH, P. O. Nilore, Islamabad 45650, Pakistan
2. Department of Physics and Applied Mathematics (DPAM), PIEAS, P. O. Nilore, Islamabad 45650, Pakistan
3. Pakistan Atomic Energy Commission (PAEC), P. O. Box 1114, Islamabad 44000, Pakistan
4. Department of Physics, Quaid-i-Azam University (QAU), Islamabad 45320, Pakistan