International Journal of

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In this work, using perturbation technique we have developed an approximate analytic model for evaluating the band structure of a 2-D octagonal photonic quasicrystal (PQC). Although numerical techniques are being used for evaluating such band structures, developing a numerical model to the best of our knowledge this work is the first instance of reporting helps to understand the physical properties of the structure more easily. Use of perturbation technique can be beneficial in approximating the photonic band structures, in PQCs made with low-dielectric contrast materials, with high accuracy. To the best of our knowledge this work is the first instance of reporting the development of such an analytic model for octagonal PQCs. In addition, we have studied the effect of variations in the dielectric contrast on the photonic band structure.

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In this article, the effect of plasmonics properties of metal nanorods and nanoparticles on solar cell performance were investigated and simulated. Due to the classic solar cell disadvantages, it seems that a plasmonic solar cell is one of these methods. In plasmonic solar cells, because of plasmonic effect, a high electric field builds around metal nanoparticles so that high conversion efficiency is available. In this study, it is shown that the near-field electromagnetic wave severely affects the generation rate, which handles the carrier’s generation in the solar cell equations. By manipulating the plasmonic properties of nanoparticles or nanorods in solar cells structure, distribution of the electromagnetic fields are altered. In this work, optical power and generation rate related to the poynting vector is calculated. So, for improving the generation rate as an important parameter in solar cells, the alteration of nanoparticles or nanorods material, shape, inter-distance between them and medium material, are done. Finally, the comparison between classical solar cell and our improved structure is performed.

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In this article, the effect of plasmonic properties of metal nanoparticles with different shapes, and moreover, their plasmonic-photonic interaction, on solar cell performance were investigated and simulated. Because of low conversion efficiency and then high cost of solar cells, it is difficult to commercialize and replace them with conventional energy resources. But in recent years, the plasmonic solar cell has been very popular. In this study, it is shown that the enhancement of near-field electromagnetic waves severely affects the generation rate, which handles the carrier’s generation in the solar cell equations and causes alteration of the photocurrent. This means that by manipulating the plasmonic properties of nanoparticles (shape and density) and their interaction with photons in solar cell structure, distribution of electromagnetic fields will be altered. Hence, the optical power related to the poynting vector is changed. So, with the aim of improving the solar cell some important parameters such as alteration of nanoparticle shape and their inter-distance were investigated. Finally, a comparison between traditional solar cells and our improved structure was undertaken.