The two-band model is improved and the nonlinear susceptibility of narrow gap semiconductors are calculated in this paper.
本文改进了半导体两带模型，计算了窄禁带半导体的非线性极化率。
2
Moreover, comparing two-band model, some new phenomena are found in our three-band model, i. e. , warping, avoided crossing etc.
并且，与两带模型比较，在三带模型中还出现一些新的现象，亦即：翘曲和避免交叉点等。
3
Within a two-band tight-binding model driven by a dc-ac electric field, we investigate the effect of external noise on the transport property of electrons in superlattices.