用B样条技术研究半导体微晶中激子的量子受限效应

在有效质量近似（EMA）下，采用B样条技术和变分方法，分别研究较大CdTe球量子点(25—35nm)和较小CdS球量子点(025—35nm)中激子的量子受限效应，计算出CdTe和CdS球量子点中受限激子的基态能和束缚能随参数的变化规律，比较两种计算结果得到：（1）较大量子点中受限激子的基态能和束缚能对量子点边界和量子点外部介质的介电常数不敏感，但较小量子点中受限激子的基态能和束缚能对量子点边界和量子点外部介质的介电常数比较敏感.（2）在较强受限区域，大量子点与小量子点的激子基态能和束缚能的变化规律完全不同.（3）B样条技术对于研究这种具有边界的束缚态系统是很精确的方法，这种方法特别适合用于多层结构量子点系统的精确计算. 关键词： B样条技术 量子受限效应 有效质量近似

Studies of quantum confinement effects of excitons in semiconductor crystallites with the B-spline technique

The behaviors of the ground-state energies and binding energies of the confined excitons in larger CdTe quantum dots(25—35nm) and the smaller CdS quantum dots(025—35nm) are studied variationally by means of the B-spline technique based on the effective mass approximation method. It is shown from the studie s that:(1) The ground-state energies and binding energies of the confined excito ns in the larger quantum dots are not sensitive to the barrier height of potenti al and the dielectric constant of surrounding material as compared to those of s mall quantum dots; (2) The behaviors of the ground-state energies and binding en ergies of the confined excitons in larger quantum dots are very different with t hose of smaller quantum dots (3)The B-spline technique is a better one to descri be the status of excitons confined by quantum wall or well, and this method is f it to calculate the multi-layer quantum dot accurately.