自组装耦合量子点中的类氢杂质

摘要

The binding energy of a hydrogenic impurity in self- assembled double quantum dots was calculated via the finite - difference method. The variation of the binding energy with structure parameters , the donor position and external magnetic field were studied in detail. The results show that the binding energy has a complex behavior due to the coupling between the two dots; it is much larger when the donor placed in the center of one dot than in the other positions; and the external magnetic field has different effects on the binding energy for different quantum dot size or lateral confinement.%在有效质量近似下,采用有限差分的方法研究了自组装耦合量子点中类氢杂质的结合能随量子点结构参数(量子点尺寸和量子点间距)和杂质位置的变化规律,并计算了外加磁场对此规律的影响.结果表明:杂质结合能随着结构的变化呈现出复杂的变化趋势；杂质位于其中一个量子点的中心位置时,体系的结合能最强；外加磁场将提高杂质的结合能,但量子点结构和杂质位置不同其影响也不同.