外电场对直接带隙Ge量子阱中的光学性质的影响

在有效质量近似下，考虑到外电场的影响，详细研究了直接带隙Ge/GeSi量子阱中带间光跃迁吸收系数和阈值能量随量子阱阱宽，外电场强度的变化情况。结果表明：随着外电场的增强，带间光跃迁吸收强度会逐渐减弱，阈值能量减小，吸收曲线向低能方向移动，出现了红移现象。此外，当量子阱比较大时，外电场对量子阱中带间光跃迁阈值能量的影响更加明显。

External electric field effects on the optical properties in direct-gap Ge quantum well

Within the framework of the effective-mass approximation, the dependence of the interband optical absorption coefficient and threshold energy on the well width and external electric field in direct-gap Ge/GeSi quantum well has been investigated in details. Numerical results indicate that when the electric field is increased, the intensity of the interband optical absorptions is reduced. Moreover, the threshold energy is decreased and the absorption peak is moved towards the lower energy. Red shift is observed. In addition, when the size of the quantum well is large, the electric field effect on the threshold energy of the interband optical transitions is more obvious.