用B样条技术研究半导体微晶中激子的量子受限效应  

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

作　　者：惠萍[1] 

机构地区：[1]广东教育学院物理系,广州510303

出　　处：《物理学报》2005年第9期4324-4328,共5页Acta Physica Sinica

基　　金：广东省自然科学基金资助(批准号:33446);广东省教育厅自然科学基金;广东教育学院教授;博士专项科研经费资助的课题.~~

摘　　要：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(2.5—35nm)和较小CdS球量子点(0.25—3.5nm)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.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 studies that ： （1） The ground-state energies and binding energies of the confined excitons in the larger quantum dots are not sensitive to the barrier height of potential and the dielectric constant of surrounding material as compared to those of small quantum dots; （2） The behaviors of the ground-state energies and binding energies of the confined excitons in larger quantum dots are very different with those of smaller quantum dots （3）The B-spline technique is a better one to describe the status of excitons confined by quantum wall or well, and this method is fit to calculate the multi-layer quantum dot accurately.

关 键 词：B样条技术 量子受限效应 有效质量近似 受限激子 B样条 半导体微晶 技术 量子点 CDTE 变化规律 介电常数 

分 类 号：O471.1[理学—半导体物理] TB383[理学—物理]