1. Waterloo Institute for Nanotechnology & Department of Electrical and Computer Engineering, University of Waterloo, Waterloo, ON N2L 3G1, Canada
2. Physics Department, University of Engineering & Technology, Lahore 54890, Pakistan
3. Department of Parasitology, University of Veterinary & Animal Sciences, Lahore 54000, Pakistan
4. Centre of Solid State Physics, Punjab University, Lahore 54590, Pakistan