Effect of hydrogen coverage on elastic and optical properties of silicene: a first-principle study

The structural, electronic, and optical properties of hydrogenated silicene have been investigated using first-principles DFT calculations. Compared to pristine silicene, hydrogenated silicene exhibits high stability, reduced anisotropy, and less birefringence. Hydrogenated silicene shows a constant refractive index in the visible region, increasing exponentially in silicene. The elastic and optical parameters such as Young's modulus (Y), Poisson's ratio (ν), bulk modulus (B), shear modulus (G), dielectric constant ε(0), refractive index n(0), conductivity threshold (E_th), birefringence Δn(0), and plasmon energy (ħω_p) were calculated for the first time for different hydrogen coverage on silicene, which is crucial in the applications of linear and non-linear optoelectronic devices. The estimated parameters agree well with the available experimental and reported values.