磁场对耦合双量子盘中类氢杂质性质的影响  

Hydrogenic-donor Impurity States in Coupled Quantum Disks in the Presence of a Magnetic Field

作　　者：杜坚[1] 李海涛[1] 刘力哲[1] 刘建军[2] 

机构地区：[1]承德民族师范高等专科学校物理系,河北承德067000 [2]河北师范大学物理科学与信息工程学院,河北石家庄050016

出　　处：《河北师范大学学报（自然科学版）》2008年第2期191-194,共4页Journal of Hebei Normal University：Natural Science

基　　金：国家自然科学基金(10674040);河北省自然科学基金(A2007000233);河北省自然科学技术革新基金(06547006D-4)

摘　　要：在有效质量近似下,采用简单的变分波函数,定量计算了无限深对称GaAs/AlGaAs耦合双量子盘在沿轴向不同强度磁场的作用下,类氢杂质体系的基态束缚能随量子盘的半径、中心垒厚、盘厚度的变化.发现,体系束缚能由空间限制作用和磁场限制作用共同决定:在空间限制比较弱时磁场强度对束缚能的影响变得更加明显,当空间限制强时磁场对束缚能的影响变得微弱.还发现,由于2个量子盘间的耦合作用使耦合双量子盘的结果比单量子盘结果偏小.在耦合双量子阱的极限条件下所得的结果与前人的结果符合得很好.Studied the binding energies of a hydrogenie-donor impurity in a cylindrically symmetric GaAs/ GaAlAs-coupled quantum disk in the presence of a uniform magnetic field for different disk and barrier thicknesses, disk radii, and donor ion positions within the disk. The magnetic field was assumed to be applied parallel to the disk axis. The calculations were performed by using a variational procedure for finite confinement potentials within the effective-mass approximation. The calculated results showed that the binding energy depended on the interplay of the spatial confinement and magnetic field confinement ：A high magnetic field significantly enhanced the binding energy in the case of weak spatial confinement. The binding energy of a hydrogenic-donor impurity in two coupled quantum disks was found to be smaller than that in a corresponding single quantum disk, due to the coupling effect between the disks. In the limits of coupled quantum wells, the results showed good agreement with those previously obtained for the case in which the donor ion was located at the center of the quantum disk.

关 键 词：对称双量子盘 类氢杂质 束缚能 磁场 

分 类 号：O572.242[理学—粒子物理与原子核物理]