1. Department of Engineering Mathematics and Physics, Faculty of Engineering, Fayoum University, Fayoum, Egypt
2. Department of Engineering Mathematics and Physics, Faculty of Engineering, Cairo University, Giza 12613, Egypt
3. Nanoelectronics Integrated Systems Center (NISC), Nile University, Giza, Egypt
4. Department of Electrical and Computer Engineering, University of Sharjah, P. O. Box 27272, Sharjah, UAE
5. Electronics Laboratory, Department of Physics, University of Patras, Rio Patras 26504, Greece