Structural and optical studies of vertically aligned InAs/GaAs self-assembled quantum dots
Structural and optical studies of vertically aligned InAs/GaAs self-assembled quantum dots
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垂直排列InAs/GaAs自组装量子点的结构和光学研究
DOI：
10.1063/1.1418003
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发表时间：
2001
影响因子：
3.2
通讯作者：
M. Hopkinson
中科院分区：
文献类型：
--
作者：
M. Migliorato;L. Wilson;D. Mowbray;M. S. Skolnick;M. Al;A. Cullis;M. Hopkinson
我们报告了多层 InAs/GaAs 自组装量子点的结构和光学光谱研究，研究了量子点层之间 GaAs 厚度的函数。随着GaAs厚度的减小，不同层中的点的位置表现出从不相关到完全相关的转变。在光学上，不相关和完全相关结构中的点被发现表现出非常独特和不同的特性。随着激光功率的增加，相关结构的光致发光表现出高能量、不对称展宽，而这种效应在不相关结构中不存在。在光致发光激发中，在不相关结构的光谱中观察到多LO-声子载流子弛豫特征，但在相关结构的光谱中观察不到。这些差异可以通过相关点结构中的点之间的非共振载流子隧穿来解释。
We report a structural and optical spectroscopic investigation of multiple layer InAs/GaAs self-assembled quantum dots, studied as a function of the GaAs thickness between the quantum dot layers. With decreasing GaAs thickness the positions of dots in different layers exhibit a transition from no correlation to full correlation. Optically the dots in uncorrelated and fully correlated structures are found to exhibit very distinct and different properties. With increasing laser power the photoluminescence of the correlated structure exhibits a high energy, asymmetrical broadening, an effect absent in the uncorrelated structure. In photoluminescence excitation multiple-LO-phonon carrier relaxation features are observed in the spectra of the uncorrelated structure but not in the spectra of the correlated structure. These differences are explained in terms of nonresonant carrier tunneling between the dots in the correlated dot structures.