纳米体系中发光能隙展宽的研究

采用两种简单的一维模型，通过直接严格求解该模型下薛定鄂方程给出晶场中的限域情况下电子能级结构以及纳米体系中电子的限域能，从而研究体系的发光蓝移现象.基于限域能的计算，讨论了纳米体系的限域能和发光蓝移随尺寸以及势场的变化关系.结果表明：导带底的电子能级随体系的尺寸增大而降低；而价带顶则随粒径的增大而升高，因此，限域能随纳米尺寸的减小迅速增大.同时将计算结果与通常文献中所采用的有效质量计算的结果进行比较，可以看出二者有明显差别，且尺寸越小，其差异越大.因此，限域能随尺寸的变化并不严格满足通过有效质量方法计算出关键词：蓝移能隙量子限域效应量子尺寸

Study of the spread of the energy gap in nanostructure systems

In recent years considerable attention is being paid to the blue-shift of photoluminescence due to quantum confinement in the nanostructure. By employing two simple models of one-dimensional crystal potential，we study the electronic energy spectra and confinement energies by solving the Schrdinger equation for the models. Based on the calculation of the confinement energies in the nanostructures，the size- and potential-dependence of the confinement energy and the blue shift are investigated. The results suggest that: with creasing size of the system the energy of electrons at the bottom of the conduction band decreases，but increases at the top of the valence band. Therefore，the confinement energies increased abruptly as the size of nano-particle (or nanostructures) decreases. Meanwhile，our results for the confinement energies show obvious difference from the ones calculated by the effective-mass approximation of ten used in the literature. Moreover，we also find that the band gap and blue shift depend on the crystal potential in the systems，and the confinement energies decrease as the potential increases.