Organic light emitting diods (OLEDs) are electronic devices fabricated with organic molecules, emitting electromagnetic radiation when biased to an electric current source. Nowadays they have wide applications in a variety of technologies because of their superior properties compared to other light emitting devices. The main goal of this project was the fabrication and optimization of OLEDs radiating near infrared light to use them in fiber-optic gyroscopes (FOGs). Today the FOGs are fabricated using superluminescent light emitting diods (SLEDs) . SLEDs are very expensive and replacing them by OLEDs can lower the costs of FOG fabrication. For fabricating high efficiency OLEDs it was necessary to investigate different mechanisms of radiation of organic molecules in OLEDs. Based on our investigations, phosphorescence and delayed fluorescence are two high efficiency radiation mechanism for organic molecules in OLEDs. So in order to acquire high efficiency OLEDs we decide to fabricated them with phosphorescent and delayed fluorescent molecules. We went through two pathways in this project. The first pathway was fabrication and structure optimization of OLEDs fabricated with the molecule Pt(tptbp), radiating with phosphorescence mechanism. In this way Pt(tptbp) was synthesized, and the respective OLED was fabricated. Also adding a layer of MoOextsubscript{3} to the structure of this OLED, hole injection to the device was optimized, and this reduced the operating voltage and increased the efficiency of the OLED. The second pathway was to find materials suitable for use in the active layer of The OLEDs radiating with delayed fluorescence mechanism. In this way, density functional theory (DFT) and time dependent density functional theory calculations were performed on more than 100 molecules, and suitable candidate for OLED fabrication were found. Also the density functional based tight binding theory (DFTB) was benchmarked as a prescreening tool for finding suitable OLED emitters and was proved to be an efficient tool in this purpose.
