自旋对非对称量子点中弱耦合束缚磁极化子基态能量的影响

J4 ›› 2011, Vol. 28 ›› Issue (4): 483-489.

自旋对非对称量子点中弱耦合束缚磁极化子基态能量的影响

汪哓武¹,肖娟²,李建红²,李志新¹

1 河北科技师范学院理化学院，河北秦皇岛 066004；
2 河北科技师范学院数学与信息科技学院, 河北秦皇岛 066004

收稿日期:2010-03-01 修回日期:2010-06-23 出版日期:2011-07-28 发布日期:2011-07-06
通讯作者: 汪晓武（1966-），安徽无为人，讲师，主要从事凝聚态光学性质方面的研究。 E-mail:zzlxx2006@126.com
基金资助:
The Doctorial Foundation of Hebei Normal University of Science and Technology(2008YB001)

Effect of spin on ground-state energy of weak-coupled bound magnetopolaron in asymmetry quantum dot

WANG Xiaowu¹, XIAO Juan², LI Jianhong² ，LI Zhixin¹

1 College of Physics and Chemistry, Hebei Normal University of Science and Technology, Qinhuangdao 066004, China；
2 College of Mathematics and Information Technologe, Hebei Normal University of Science and Technology, Qinhuangdao 066004, China

Received:2010-03-01 Revised:2010-06-23 Published:2011-07-28 Online:2011-07-06
Supported by:
The Doctorial Foundation of Hebei Normal University of Science and Technology(2008YB001)

摘要/Abstract

摘要：

采用Tokuda修正的线性组合算符和幺正变换方法，研究了非对称量子点中弱耦合束缚磁极化子的性质。推导出了磁极化子基态能量随量子点横向、纵向受限长度和磁场的变化关系。进行了数值计算，计算结果表明：考虑自旋影响时，束缚磁极化子基态能量分裂成自旋向上（向下）两个分支。并且磁极化子基态能量、自旋向上（向下）分裂能随量子点横向、纵向受限长度的增加而减少，随磁场强度的增加而增大。

关键词: 光电子学, 非对称量子点, 自旋电子学, 弱耦合, 束缚磁极化子

Abstract:

The properties of bound magnetopolaron, which is weakly coupled to LO-phonon in an asymmetric quantum dot (QD) were studied by using Tokuda modified linear combination operator and unitary transformation methods. The expression of the ground-state energy as functions of the transverse and longitudinal confinement lengths and the magnetic field was derived. After a simple numerical calculation, it's found that he ground-state energy of bound magnetopolaron splits into two branches after taking into account the spin influence. The ground-state energy, spin-up(down) splitting energy decrease with increasing the transverse and longitudinal confinement lengths, and it is an increasing function of magnetic field.

Key words: optoelectronics, asymmetric quantum dot, spintronics, weak-coupled, bound magnetopolaron

中图分类号:

O469
O472.3

汪哓武肖娟李建红李志新. 自旋对非对称量子点中弱耦合束缚磁极化子基态能量的影响[J]. J4, 2011, 28(4): 483-489.

WANG Xiaowu, XIAO Juan, LI Jianhong，LI Zhixin . Effect of spin on ground-state energy of weak-coupled bound magnetopolaron in asymmetry quantum dot [J]. J4, 2011, 28(4): 483-489.

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