First-principles calculations of electronic structure and optical properties of strained Mg2Si

Abstract

A detailed theoretical study on structural, electronic and optical properties of Mg 2 Si under the isotropic lattice deformation was performed based on the first-principles pseudopotential method. The results show that the isotropic lattice deformation results in a linear decrease in the energy gap for the direct Γ 15 -Γ 1 and indirect Γ 15 -L 1 transitions from 93% to 113%, while the indirect band gap Γ 15 -X 1 increases from 93% to 104% and then reduces over 104%. When the crystal lattice is 93% compressed and 113% stretched, the magnesium silicide is a zero-gap semiconductor. Furthermore, the isotropic lattice deformation makes the dielectric function shift and the static dielectric constant change. magnesium silicide, strain, first-principles, band structure, dielectric function Citation:Chen Q, Xie Q, Zhao F J, et al. First-principles calculations of electronic structure and optical properties of strained Mg 2 Si.

Systematic Theoretical Study on Structural, Stability, Electronic, and Spectral Properties of Si2MgnQ (Q = 0, ±1; n = 1–11) Clusters of Silicon-Magnesium Sensor Material

“…Aymerich and Mula (2010) and Imai et al (2003) studied the band structure of Mg 2 Si using empirical and first-principles pseudopotentials, respectively. Chen et al (2010) studied the band structure of Mg 2 Si and doped Ag, Al elements by using the first-principles pseudopotential plane wave method based on density functional theory (DFT). By using DFT, they obtained the real part, imaginary part and Photoconductivity of Mg 2 Si dielectric function as a function of photon energy.…”

Influences of Nd doping on preparing Mg 2 Si semiconductor thin films by thermal evaporation

“…Recently, most researchers in the academic circle have been devoted to the experimental and theoretical research on the thermoelectric properties of doped Mg 2 Si bulk or powder [4][5][6][7][8][9][10]. However, doped Mg 2 Si thin films have rarely been reported.…”

Thermoelectric and electrical transport properties of Mg2Si multi-doped with Sb, Al and Zn

“…The efficiency of thermoelectric materials can be enhanced through p-or n-type doping. [5][6][7][8][9] Dopants can increase the carrier concentration and mobility of the conduction electrons. Doping with heavy atoms can also affect the lattice vibrations and help to lower the thermal conductivity.…”