Zn_(1-x)Cd_xSe/ZnSe的量子Stark效应的变分法研究

Variational method study of quantum-confined Stark effect in the Zn_(1-x)Cd_xSe/ZnSe quantum well

用变分法计算了在不同量子阱宽度、不同外电场强度下 ,Zn0 .8Cd0 .2 Se/ Zn Se量子阱中电子、空穴基态能量及激子束缚能的变化规律 ,并根据所得的 Ee、Eh 和 Eb 数据 ,计算出激子吸收峰的 Stark移动 .计算结果显示 ,随着外电场强度和量子阱宽度的增大 ,量子 Stark效应变得更为显著 .本文还把计算所得的 Stark移动与从激子吸收光谱曲线中得到的实验数据进行了比较 ,当阱宽等于 9nm、电场为 10 0 k V/ cm时 ,两者符合得较好 .

The variation method was used to calculate the lowest eigenenergy of electrons and holes and the binding energy of excitons in Ⅱ Ⅵ quantum well Zn 0.8 Cd 0.2 Se/ZnSe for different well widths and different electric fields. The obtained data on E e, E h and E b were used to compute the Stark shift of the exciton absorption peak. The theoretical results showed that the Stark effect becomes more remarkable with the increase of the electric field and well width. Comparison of the calculated Stark shift with the experimental value obtained from the absorption line shape showed good agreement when well width was about 9 nm and the electric field was about 100 kV/cm.