A hybrid functional first-principles study on the band structure of non-strained Ge_1-xSn_x alloys

【摘要】 Using hybrid-functional first-principles calculation combined with the supercell method and band unfolding technique we investigate the band structure of non-strained Ge_1-xSn_x alloys with various Sn concentrations. The calculations show that at the Sn concentration of ～ 3.1 mol% the Ge Sn alloy presents a direct band gap. The variation of the band structure are ascribed to the weaker electro-negativity of Sn atoms and a slight charge transfer from Sn atoms to Ge atoms.更多还原

【Abstract】 Using hybrid-functional first-principles calculation combined with the supercell method and band unfolding technique we investigate the band structure of non-strained Ge_1-xSn_x alloys with various Sn concentrations. The calculations show that at the Sn concentration of ～ 3.1 mol% the Ge Sn alloy presents a direct band gap. The variation of the band structure are ascribed to the weaker electro-negativity of Sn atoms and a slight charge transfer from Sn atoms to Ge atoms.更多还原