عنوان مقاله [English]
نویسندگان [English]چکیده [English]
2-dimensional layers of transition metal dichalcogenids (TMDCs) with direct band gap in the visible and infrared range have shown open horizon in photonics and optoelectronics. Among TMDC family, MoSe2, WSe2, MoS2 and WS2 monolayers have shown special optical properties. In this paper, the permittivity constant of aforementioned monolayers are calculated based on Lorentz, Lorentz- Gauss and Lorentz –Drude-Gauss models with quite acceptable consistency to their experimental values. Optical absorption response of these photovoltaic monolayers is similar to imaginary component of their permittivity. In addition, based on investigation of optical absorption in presence of substrates, it is found that the absorption decreases which is more pronounced while refractive index of substrates increases. Such thin layers with absorption efficiency above 10% with thickness below 1 nm are suitable candidates for solar cell and photovoltaic applications.
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