A detailed theoretical study on structural,electronic and optical properties of Mg2Si under the isotropic lattice deformation was performed based on the first-principles pseudopotential method.The results show that th...A detailed theoretical study on structural,electronic and optical properties of Mg2Si 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 directΓ15-Γ1 and indirectΓ15-L1 transitions from 93%to 113%,while the indirect band gapΓ15-X1 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.展开更多
基金supported by the National Natural Science Foundation of China(60566001,60766002)the Major International Joint Research Program from the Ministry of Science and Technology of China (2008DFA52210)+1 种基金the Project of Guizhou Province Information Industry Department(0831)the Undergraduate Carve Out Project of Bureau of Guiyang Science and Technology(6-5)
文摘A detailed theoretical study on structural,electronic and optical properties of Mg2Si 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 directΓ15-Γ1 and indirectΓ15-L1 transitions from 93%to 113%,while the indirect band gapΓ15-X1 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.
