Origins of Spectral Diffusion in the Micro-Photoluminescence of Single InGaN Quantum Dots
Origins of Spectral Diffusion in the Micro-Photoluminescence of Single InGaN Quantum Dots
复制标题
单 InGaN 量子点微光致发光中光谱扩散的起源
DOI：
10.7567/jjap.52.08je01
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发表时间：
2013
影响因子：
1.5
通讯作者：
R. Taylor
中科院分区：
文献类型：
--
作者：
B. Reid;T. Zhu;T. Puchtler;Luke J. Fletcher;Christopher C. S. Chan;R. Oliver;R. Taylor
我们报告了在具有不同螺纹位错密度的三个 GaN 赝衬底上生长的自组装 InGaN 量子点 (QD) 的光学特性。 QD 密度是通过在带有圆形孔图案的掩模样品上的显微光致发光来估计的，并且似乎随着位错密度的增加而增加。使用非线性激发技术来观察 QD 发射的尖锐谱线特征。观察到单个量子点发射波长的时间变化，并将其归因于光谱扩散。这些时间变化的幅度随着位错密度的增加而增加，这表明由于位错捕获的电荷而引起的局部波动电场是该系统中光谱扩散的原因。
We report on optical characterization of self-assembled InGaN quantum dots (QDs) grown on three GaN pseudo-substrates with differing threading dislocation densities. QD density is estimated via microphotoluminscence on a masked sample patterned with circular apertures, and appears to increase with dislocation density. A non-linear excitation technique is used to observe the sharp spectral lines characteristic of QD emission. Temporal variations of the wavelength of emission from single QDs are observed and attributed to spectral diffusion. The magnitude of these temporal variations is seen to increase with dislocation density, suggesting locally fluctuating electric fields due to charges captured by dislocations are responsible for the spectral diffusion in this system.