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The effect of the presence of electron-phonon (e-ph) coupling in the S iC, GeC and S nC hybrids is studied in the framework of the ab initio perturbation theory. The electronic bang gap thermal dependence reveals a normal monotonic decrease in the S iC and GeC semiconductors, whereas S nC exhibits an anomalous behavior. The electron line widths were evaluated and the contributions of acoustic and optical phonon modes to the imaginary part of the self-energy were determined. It has been found that the e-ph scattering rates are globally controlled by the out-of-plane acoustic transverse mode ZA in SiC while both ZA and ZO are overriding in GeC. In S nC, the out-of-plane transverse optical mode ZO is the most dominant. The relaxation lifetime of the photo-excited electrons shows that the thermalization of the hot carrier occurs at 90 f s, 100 f s and 120 f s in S iC, GeC and S nC respectively. The present study properly describes the subpicosecond time scale after sunlight illumination using an approach that requires no empirical data. The results make the investigated structures suitable for providing low cost and high-performance optical communication and monitoring applications using 2D materials.

The present paper is a systematic analysis of the thermoelectric and optical properties of the SiC monolayer. Based on the density functional theory (DFT) combined with the Boltzmann transport theory, the thermal conductivity, the electrical conductivity and the figures of merit are all determined and discussed for the SiC hybrid. At room temperature, it is found that SiC shows interesting values with respect to its counterparts graphene and silicene. To improve the absorption of the SiC sheet, a strategy is proposed using finite-difference time-domain (FDTD) combing with PSO-based approach. The absorbance of the UV-photodector with SiC monolayer and the SiC-based photodector with Au plasmonic grating are studied. Among our findings, the Au plasmonic grating enhances the absorbance of SiC to reach a maximum absorbance of 99.6% at the resonance wavelength of (λ = 310 nm), which significantly improves the performance of UV-sensors. Therefore, by combining optical DFT analysis with FDTD simulation supported by global PSO optimization, we have been able to develop a new SiC monolayer high performance UV photodetector suitable for advanced optoelectronic applications.

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