介电受限对CdSe量子点中受限激子的影响

EFFECTS OF DIELECTRIC CONFINEMENT ON EXCITIONIC STATES IN CdSe QUANTUM DOT 

在有效质量近似条件下，通过Ｗａｎｇ和Ｚｕｎｇｅｒ给出的ＣｄＳｅ量子点介电常量与其半径的关系，利用变分方法计算了该量子点中受限激子的基态能及束缚能．结果表明，在考虑量子点介电常量随尺度减小的变化以后，受限激子的束缚能增大，基态能降低，更接近实验值．同时，也讨论了量子点介电常量的尺度效应和表面极化效应对受限激子的影响．

Abstract According to the relationship of Wang and Zunger between the declectric constants and the radius of a CdSe quantum dot (QD),we use the variational method to calculate the binding energy and ground state energy of an exciton in the QD.Compared with the previouse calculations,the present result shows that the binding energy increases while its ground state energy becomes lower and it is close to the experimental value.