1. Faculty of Electrical Engineering, Universiti Teknologi MARA, Cawangan Pulau Pinang, 13500, Permatang Pauh, Penang, Malaysia
2. Department of Applied Sciences, Universiti Teknologi MARA, Cawangan Pulau Pinang, 13500, Permatang Pauh, Penang, Malaysia
3. Nano-Optoelectronics Research And Technology Laboratory (N.O.R.), School of Physics, Universiti Sains Malaysia, 11800, Pulau Pinang, Malaysia