Using hybrid-functional first-principles calculation combined with the supercell method and band unfolding technique we investigate the band structure of non-strained Ge1-xSnx alloys with various Sn concentrations. Th...Using hybrid-functional first-principles calculation combined with the supercell method and band unfolding technique we investigate the band structure of non-strained Ge1-xSnx alloys with various Sn concentrations. The calculations show that at the Sn concentration of^3.1 mol% the GeSn 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.展开更多
基金Project supported by the Scientific Research Foundation for the Returned Overseas Chinese Scholars of the State Education Ministry of China(Grant No.[2015]-1098)the Open Project of the State Key Laboratory of Surface Physics of Fudan University,the Natural Science Foundation of Guangdong Province of China(Grant No.2016A030307038)the University Innovating and Strengthening Project of Department of Education of Guangdong Province,China(Grant No.2015KTSCX090)
文摘Using hybrid-functional first-principles calculation combined with the supercell method and band unfolding technique we investigate the band structure of non-strained Ge1-xSnx alloys with various Sn concentrations. The calculations show that at the Sn concentration of^3.1 mol% the GeSn 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.