Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7938949 | Superlattices and Microstructures | 2018 | 9 Pages |
Abstract
In this paper, we theoretically study the optical properties of both bulk and monolayer MoS2 using first-principles calculations. The optical characters such as: dielectric function, optical reflectivity, and electron energy-loss spectrum of MoS2 are observed in the energy region from 0 to 15â¯eV. At equilibrium state the dielectric constant in the parallel Eâ¥x and perpendicular Eâ¥z directions are of 15.01 and 8.92 for bulk while they are 4.95 and 2.92 for monolayer MoS2, respectively. In the case of bulk MoS2, the obtained computational results for both real and imaginary parts of the dielectric constant are in good agreement with the previous experimental data. In the energy range from 0 to 6â¯eV, the dielectric functions have highly anisotropic, whereas they become isotropic when the energy is larger than 7â¯eV. For the adsorption spectra and optical reflectivity, both the collective plasmon resonance and (Ï+Ï) electron plasmon peaks are observed, in which the transition in Eâ¥x direction is accordant with the experiment data more than the transition in Eâ¥z direction is. The refractive index, extinction index, and electron energy-loss spectrum are also investigated. The observed prominent peak at 23.1â¯eV in the energy-loss spectra is in good agreement with experiment value. Our results may provide a useful potential application for the MoS2 structures in electronic and optoelectronic devices.
Keywords
Related Topics
Physical Sciences and Engineering
Materials Science
Electronic, Optical and Magnetic Materials
Authors
Nguyen N. Hieu, Victor V. Ilyasov, Tuan V. Vu, Nikolai A. Poklonski, Huynh V. Phuc, Le T.T. Phuong, Bui D. Hoi, Chuong V. Nguyen,