الفهرس 
Chapter 1Only 14 pages are availabe for public view
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Abstract
The photonics world is becoming increasingly interested in plasmonic photodetectors. In other words, the field of plasmonics allows light to be dedicated to small spaces in metallic structures. This property can therefore simulate extra improvements in the performance of photodetectors. Because of the short absorption length of Gallium arsenide (GaAs), its substrate has a wide bandwidth range and high responsivity attributes. It can gather and generate light more efficiently than semiconductors’ indirect band gaps since it is a semiconductor’s direct band gap. In this thesis, it is presented that gold (Au) and aluminum (Al) surface plasmon polariton (SPP) GaAs PIN photodetector achieved higher internal quantum efficiency (IQE). At a wavelength of 870 nm, the IQE with Au and Al SPP rectangle grating is 95.01%, while the IQE of a standard GaAs photodetector without SPP grating is 42%, which indicates an improvement of 53.01%. Also, the IQE with the Au SPP rectangle grating is 85%, whereas the IQE is enhanced by 10.01% in the case of the Au and Al SPP rectangle grating model. In addition, nanogratings of various shapes, such as triangular, ellipse, bowtie, and circle are studied, which increase the IQE of the proposed photodetector up to 98.48%, with a total enhancement IQE of 56.48% over the model of the standard GaAs photodetector without the SPP grating and an enhancement of 13.48% over the Au SPP rectangle grating model. Moreover, output current and responsivity are enhanced. This remarkable enhancement is achieved with bowtie grating as compared to other shapes. Different metallic concerning wavelength of light and nanostructures geometry, subwavelength slit structures have plasmonic impacts and could develop a high light intensity region. In this thesis, GaAs PIN photodetector with different nanoparticles (NPs) SPP such as tungsten (W), palladium (Pd), mercury (Hg), rhodium (Rh), bismuth (Bi), copper (Cu), tin (Sn), gold (Au), and aluminum (Al) are studied, which improves the performance of the PIN GaAs modelled photodetector. Internal quantum efficiency [IQE] with the Al SPP grating is 90.76%, whereas the IQE of the Au SPP grating is 85%, which demonstrated an enhancement of 5.76%. Furthermore, the IQE of the proposed GaAs photodetector with no SPP grating is 42.00%, with a total improvement in IQE of 48.76% achieved by the proposed Al SPP grating photodetector in comparison with different other NPs. Moreover, the distinctive enhancement in photocurrent and responsivity.