摘要
使用第一性原理和赝势方法研究了Ge_(50)Sn_(50)有序合金直到9 GPa压力下的能带结构和带隙的压力依赖性。发现该合金的直接带隙随着压力的增大几乎是线性增加,在4.7 GPa时达到最大值0.72 eV;在该压力下发生直接带隙至间接带隙的转变,其导带在4.7 GPa-8 GPa时与Ge类似,在高于6.8 GPa压力时与Si类似。同时还研究了自旋轨道耦合作用对合金能带结构的影响。
First principles and pseudopotential approaches have been used to investigate band structures and pressure dependence of the band-gaps of ordered zincblende Ge50Sn50 alloy up to 9 GPa. It is found that the direct band-gap increases almost linearly with pressure to a maximum value 0.72 eV at 4.7 GPa where direct to indirect transition of the band-gap takes place. The conduction band is similar to that of Ge in the range of 4.7 GPa～5.8 GPa and similar to that of Si when the pressure is higher than 6.8 GPa. At the same time, the influence that spin-orbit coupling affects the band structure of the alloy has been discussed.
出处
《燕山大学学报》
CAS
2007年第3期198-200,共3页
Journal of Yanshan University
基金
国家杰出青年科学基金项目(No.50325103)
