Optical properties of single InGaN quantum dots and their devices
Optical properties of single InGaN quantum dots and their devices
复制标题
单InGaN量子点及其器件的光学特性
DOI：
10.1002/pssb.201147143
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发表时间：
2011
期刊：
影响因子：
--
通讯作者：
J. Gutowski
中科院分区：
文献类型：
--
作者：
K. Sebald;J. Kalden;H. Lohmeyer;J. Gutowski
基于氮化物的量子点对于实现基于量子点（QD）的器件具有许多有吸引力的光学特性，这些特性将在本贡献中介绍。我们将分析单个 InGaN QD 的基本特性及其电致发光 (EL) 以及 QD 堆叠的光学特性及其增益光谱。单量子点的特点是在 PL 和 EL 中发射高达 150 K 的高温稳定性，对于堆叠 QD 样品甚至可以达到室温。此外，还分析了各个量子点发射线的偏振，以深入了解其几何形状。对单个量子点的激子和双激子跃迁以及压电场对其及其结合能的影响进行了时间分辨微光致发光（μ-PL）测量。此外，我们对嵌入发光二极管结构中的单个 InGaN QD 的电驱动发光进行了分析，显示了绿色光谱区域中的单个锐发射线，具有高达 150 K 的高温稳定性。此外，为了将来可能集成到光学器件中，研究了具有堆叠 InGaN QD 层的样品的阈值功率密度和模态增益。它们显示出每个 QD 的模态增益与 II-VI 和 III-As 化合物相当。这些结果使人们能够深入了解基于 InGaN QD 的器件的基本光学特性，并显示出它们在电驱动单光子发射器以及在不久的将来用于明亮、低阈值的基于 InGaN QD 的发光器件的巨大潜力。
Nitride‐based quantum dots have many attractive optical properties for the realization of quantum dot (QD) based devices which will be presented in this contribution. We will analyze the basic characteristics of single InGaN QDs and their electroluminescence (EL) as well as the optical properties of QD stacks and their gain spectra. The single QDs are characterized by the high temperature stability of their emission up to 150 K in PL and EL and even up to room temperature for stacked QD samples. Furthermore, the polarization of individual QD emission lines was analyzed giving an insight into their geometrical shape. Time‐resolved microphotoluminescence (µ‐PL) measurements on the excitonic and biexcitonic transition of a single QD as well as on the influence of piezoelectric fields on them and on their binding energy were performed. Further, we present an analysis of electrically driven luminescence from single InGaN QDs embedded into a light emitting diode structure showing single sharp emission lines in the green spectral region with a high temperature stability up to 150 K. Furthermore, for the possible integration within optical devices in the future the threshold power density as well as the modal gain were investigated for samples with stacked InGaN QD layers. They show a modal gain per QD being comparable to that of II–VI and III‐As compounds. These results give a good insight into the basic optical properties of InGaN QD based devices and showing their high potential for electrically driven single photon emitters as well as for bright, low‐threshold InGaN QD based light emitting devices in the near future.